View Filing Data

(161)

$ (161)

Balance (in shares) at Jun. 30, 2015

21,121

Balance at Jun. 30, 2015

$ 4

287,152

(222)

(119,990)

166,944

39,297,539

Issuance of Common Stock upon exercise of employee and non-employees stock-based awards

^[1]

2,973

Issuance of Common Stock upon exercise of employee and non-employee stock options, shares

1,592,383

Equity based compensation expenses to employees and non-employee consultants

9,089

493

Balance (in shares) at Jun. 30, 2016

76,609

Balance at Jun. 30, 2016

$ 4

299,214

271

(43,381)

256,108

40,889,922

Issuance of Common Stock upon exercise of employee and non-employees stock-based awards

^[1]

349

Issuance of Common Stock upon exercise of employee and non-employee stock options, shares

286,150

Issuance of Common stock under employee stock purchase plan

^[1]

935

Issuance of Common stock under employee stock purchase plan, share

83,319

Equity based compensation expenses to employees and non-employee consultants

6,600

(595)

Balance (in shares) at Dec. 31, 2016

25,381

Balance at Dec. 31, 2016

$ 4

307,098

(324)

(18,000)

288,778

41,259,391

Issuance of Common Stock upon exercise of employee and non-employees stock-based awards

^[1]

4,854

Issuance of Common Stock upon exercise of employee and non-employee stock options, shares

2,368,152

Issuance of Common stock under employee stock purchase plan

^[1]

2,386

Issuance of Common stock under employee stock purchase plan, share

185,058

Equity based compensation expenses to employees and non-employee consultants

17,564

(287)

Balance (in shares) at Dec. 31, 2017

84,172

Balance at Dec. 31, 2017

$ 4

$ 331,902

$ (611)

$ 66,172

$ 397,467

43,812,601

[1]	Represents an amount less than $1.

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) $ in Thousands	12 Months Ended
	Jun. 30, 2015 USD ($)
Issuance of common stock in initial public offering, issuance expenses	$ 13,692
Series E Convertible Preferred Stock [Member]
Issuance of Convertible Preferred stock, issuance expenses	$ 288

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Cash flows provided by operating activities:
Net income	$ 25,381	$ 84,172	$ 76,609	$ 21,121
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, equipment and intangible assets	2,759	7,155	3,847	2,253
Amortization of premium and accretion of discount on available-for-sale marketable securities	681	2,061	532
Stock-based compensation	6,600	17,564	9,089	2,956
Financial income, net related to term loan				(992)
Remeasurement of warrants to purchase convertible preferred stock				5,350
Capital loss from disposal of property				104
Changes in assets and liabilities:
Inventories	14,022	(15,690)	(7,356)	(48,507)
Prepaid expenses and other accounts receivable	(367)	(21,937)	10,542	(19,563)
Trade receivables, net	1,555	(38,139)	(37,271)	(16,333)
Deferred tax assets, net	3,652	(5,455)	(6,380)
Trade payables	(14,464)	35,455	(32,200)	41,111
Employees and payroll accruals	2,996	9,394	3,278	1,668
Warranty obligations	7,183	20,436	19,313	13,698
Deferred revenues	1,335	14,106	8,578	3,989
Accrued expenses, other accounts payable and non-current tax liabilities	(1,999)	27,839	3,934	2,530
Lease incentive obligation	(236)	(296)	(88)	2,669
Net cash provided by operating activities	49,098	136,665	52,427	12,054
Cash flows from investing activities:
Purchase of property and equipment	(11,025)	(21,382)	(15,690)	(11,765)
Purchase of intangible assets	(600)		(800)
Decrease (increase) in restricted cash	31	(619)	2,711	(2,038)
Decrease (increase) in long-term lease deposit	(77)		103	(134)
Investment in available-for-sale marketable securities	(40,858)	(143,675)	(118,511)
Maturities of available-for-sale marketable securities	32,782	80,269	6,350
Net cash used in investing activities	(19,747)	(85,407)	(125,837)	(13,937)
Cash flows from financing activities:
Proceeds from short term bank loan				23,000
Repayment of short term bank loan				(36,326)
Repayments of term loan				(5,919)
Proceeds from issuance of Series E Convertible Preferred stock, net				24,712
Proceeds from initial public offering, net				131,402
Issuance costs related to initial public offering			(194)
Proceeds from issuance of shares under stock purchase plan and upon exercise of stock-based awards	1,284	7,240	2,973	84
Net cash provided by financing activities	1,284	7,240	2,779	136,953
Increase (decrease) in cash and cash equivalents	30,635	58,498	(70,631)	135,070
Cash and cash equivalents at the beginning of the period	74,032	104,683	144,750	9,754
Effect of exchange rate differences on cash and cash equivalents	16	(18)	(87)	(74)
Cash and cash equivalents at the end of the period	104,683	163,163	74,032	144,750
Supplemental disclosure of non-cash investing and financing activities:
Net change in accrued expenses and other accounts payable related to property and equipment additions		598	1,187
Deferred issuance costs related to initial public offering				194
Cashless exercise of warrants to purchase common stock				6,115
Supplemental disclosure of cash flow information:
Cash paid for interest				896
Cash paid for income taxes	$ 1,103	$ 3,100	$ 1,178	$ 4,040

GENERAL

12 Months Ended

Dec. 31, 2017

Organization, Consolidation and Presentation of Financial Statements [Abstract]

GENERAL

NOTE 1:-

GENERAL

SolarEdge Technologies, Inc. (the “Company”) and its subsidiaries design, develop, and sell an intelligent inverter solution designed to maximize power generation at the individual photovoltaic (“PV”) module level while lowering the cost of energy produced by the solar PV system and providing comprehensive and advanced safety features. The Company’s products consist mainly of (i) power optimizers designed to maximize energy output from each and every module through constant tracking of Maximum Power Point individually per module; (ii) inverters which convert direct current (DC) from the PV module to alternating current (AC); (iii) a related cloud-based monitoring platform that collects and processes information from the power optimizers and inverters of a solar PV system to enable customers and system owners, as applicable, to monitor and manage the solar PV systems; and (iv) a storage solution that is used to increase energy independence and maximize self-consumption for homeowners by utilizing a battery that is sold separately by third-party manufacturers, to store and supply power as needed (the “StorEdge solution”). The StorEdge solution is designed to provide smart energy functions such as maximizing self-consumption, Time-of-Use programming for desired hours of the day, and home energy backup solutions. In addition, the Company offers several communication and smart energy management solutions.

The Company and its subsidiaries sell their products worldwide through large distributors and electrical equipment wholesalers to smaller solar installers, as well as directly to large solar installers and engineering, procurement and construction firms (“EPCs”).

Basis of presentation:

Effective December 31, 2016, the Company changed its fiscal year end from June 30 to December 31. This change was made in order to align the Company’s fiscal year end with other companies within the industry. As a result of this change, the consolidated financial statements include presentation of the six month transition period from July 1, 2016 through December 31, 2016. The Company refers to the period beginning July 1, 2015 and ending June 30, 2016 as “fiscal 2016” and the period beginning July 1, 2014 and ending June 30, 2015 as “fiscal 2015”.

Initial Public Offering:

On March 31, 2015, the Company closed its initial public offering (“IPO”) whereby 8,050,000 shares of common stock were sold by the Company to the public (inclusive of 1,050,000 shares of common stock pursuant to the full exercise of an overallotment option granted to the underwriters). The aggregate net proceeds received by the Company from the offering were approximately $131,208, net of underwriting discounts and commissions and offering expenses. Upon the closing of the IPO, all shares of the Company’s outstanding convertible preferred stock automatically converted into 28,247,923 shares of common stock, and outstanding warrants to purchase convertible preferred stock automatically converted into warrants to purchase 187,671 shares of common stock (See Note 10).

For the year ended December 31, 2017 and the six months ended December 31, 2016, the Company had one major customer (customer with attributable revenues that represents more than 10% of total revenues) that accounted for approximately 14.8% and 11.2% of the Company’s consolidated revenues, respectively (see Note 20), and for the years ended June 30, 2016 and 2015, the Company had three and one major customers that accounted for approximately 32.5% and 24.6% of the Company’s consolidated revenues, respectively (see Note 20).

The Company depends on three contract manufacturers and several limited or single source component suppliers. Reliance on these vendors makes the Company vulnerable to possible capacity constraints and reduced control over component availability, delivery schedules, manufacturing yields, and costs.

These contract manufacturers collectively accounted for 51.6%, 61% and 69% of the Company’s total trade payables as of December 31, 2017, 2016 and June 30, 2016, respectively.

The Company has the right to offset its payables to one of its contract manufacturers against vendor non-trade receivables. As of December 31, 2017, a total of $3,180 of these receivables met the criteria for net recognition and were offset against the corresponding accounts payable balances for this contract manufacturer in the accompanying Consolidated Balance Sheets.

SIGNIFICANT ACCOUNTING POLICIES

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

SIGNIFICANT ACCOUNTING POLICIES

NOTE 2:-

SIGNIFICANT ACCOUNTING POLICIES

The consolidated financial statements are prepared according to United States generally accepted accounting principles (“U.S. GAAP”).

Principles of consolidation:

The consolidated financial statements include the accounts of the Company and its subsidiaries. Intercompany transactions and balances including profits from intercompany sales not yet realized outside the Company have been eliminated upon consolidation.

Use of estimates:

The preparation of financial statements, in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The Company evaluates its assumptions on an ongoing basis, including those related to warranty obligation, inventory valuation, contingencies, share-based compensation cost, marketable securities, deferred tax assets and liabilities, intangible assets and estimates used in applying the revenue recognition policy. The Company’s management believes that the estimates, judgment, and assumptions used are reasonable based upon information available at the time they are made. These estimates, judgments, and assumptions can affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the dates of the consolidated financial statements, and the reported amounts of revenue and expenses during the reporting periods. Actual results could differ from those estimates.

Financial statements in U.S. dollars:

The functional currency of the Company and its subsidiaries (with the exception of Germany, Australia, and Japan) is the U.S. dollar, as the U.S. dollar is the currency of the primary economic environment in which the Company has operated and expects to continue to operate in the foreseeable future. Currently, the operations of these subsidiaries and the Company are primarily conducted in Israel, and a significant portion of its expenses are paid in U.S. dollars. Financing activities, including loans and cash investments are primarily made in U.S. dollars.

Accordingly, monetary accounts maintained in currencies other than the U.S. dollar are translated into U.S. dollars in accordance with Financial Accounting Standards Board Accounting Standards Codification (“ASC”) 830 (“Foreign Currency Matters”). All transaction gains and losses of the re-measurement of monetary balance sheet items are reflected in the statements of operations as financial income or expenses, as appropriate.

The financial statements of other Company’s subsidiaries whose functional currency is other than the U.S. dollar have been translated into U.S dollars. Assets and liabilities have been translated using the exchange rates in effect on the balance sheet date. Statements of operations amounts have been translated using the average exchange rate for the relevant periods.

The resulting translation adjustments are reported as a component of stockholders’ equity in accumulated other comprehensive income.

Accumulated other comprehensive loss related to foreign currency translation adjustments, net amounted to $178, $207, and $29 as of December 31, 2017 and 2016, and June 30, 2016, respectively.

Basic and Diluted Net Earnings Per Share:

Basic net earnings per share is computed by dividing the net earnings by the weighted-average number of shares of common stock outstanding during the period.

Diluted net earnings per share is computed by giving effect to all potential shares of common stock, including stock options and convertible preferred stock, to the extent dilutive, all in accordance with ASC No. 260, "Earnings Per Share."

The total weighted average number of shares related to the outstanding stock options, convertible preferred stock and warrants to purchase convertible preferred stock, excluded from the calculation of diluted net earnings per share due to their anti-dilutive effect was 197,516, 374,156, 16,208, and 20,565,747 for the year ended December 31, 2017, the six months ended December 31, 2016 and the years ended June 30, 2016 and 2015, respectively.

Basic and diluted earnings per share is presented in conformity with the two-class method for participating securities for the periods prior to their conversion. Under this method, the earnings per share for each class of shares are calculated assuming 100% of the Company’s earnings are distributed as dividends to each class of shares based on their contractual rights.

The following table presents the computation of basic and diluted net earnings per share for the periods presented (in thousands, except share and per share data):

	Year ended		Six months Ended		Year ended June 30,
	December 31, 2017		December 31, 2016		2016		2015
Net basic earnings (loss) per share of common stock:
Numerator:
Net income	$	84,172	$	25,381	$	76,609	$	21,121
Dividends accumulated for the period		-		-		-		(17,550	)
Net income available to shareholders of common stock		84,172		25,381		76,609		3,571

Denominator:
Shares used in computing net earnings per share of common stock, basic		42,209,238		41,026,926		39,987,935		11,902,911

Net diluted earnings per share of common stock:
Numerator:
Net income		84,172		25,381		76,609		21,121
Dividends accumulated for the period		-		-		-		(16,971	)
Net income available to shareholders of common stock		84,172		25,381		76,609		4,150

Denominator:
Shares used in computing net earnings per share of common stock, basic		42,209,238		41,026,926		39,987,935		11,902,911
Effect of stock-based awards		3,216,069		2,812,416		4,388,140		3,366,537
Shares used in computing net earnings per share of common stock, diluted		45,425,307		43,839,342		44,376,075		15,269,448

Basic net income per share	$	1.99	$	0.62	$	1.92	$	0.30
Diluted net income per share	$	1.85	$	0.58	$	1.73	$	0.27

Cash and cash equivalents:

Cash equivalents are short-term, highly liquid investments that are readily convertible to cash, with original maturities of three months or less at the date acquired.

Marketable Securities:

Marketable securities consist of corporate and governmental bonds. The Company determines the appropriate classification of marketable securities at the time of purchase and re-evaluates such designation at each balance sheet date. In accordance with FASB ASC No. 320 “Investments - Debt and Equity Securities”, the Company classifies marketable securities as available-for-sale. Available-for-sale securities are stated at fair value, with unrealized gains and losses reported in accumulated other comprehensive income (loss), a separate component of stockholders’ equity, net of taxes.

Realized gains and losses on sales of marketable securities, as determined on a specific identification basis, are included in financial income (expenses), net. The amortized cost of marketable securities is adjusted for amortization of premium and accretion of discount to maturity, both of which, together with interest, are included in financial income (expenses), net.

The Company classifies its marketable debt securities as either short-term or long-term based on each instrument’s underlying contractual maturity date. Marketable debt securities with maturities of 12 months or less are classified as short-term and marketable debt securities with maturities greater than 12 months are classified as long-term.

The Company recognizes an impairment charge when a decline in the fair value of its investments in debt securities below the cost basis of such securities is judged to be other-than-temporary. Factors considered in making such a determination include the duration and severity of the impairment, the reason for the decline in value, the potential recovery period, and the Company’s intent to sell, including whether it is more likely than not that the Company will be required to sell the investment before recovery of cost basis. If the Company does not intend to sell the security or it is not more likely than not that it will be required to sell the security before it recovers in value, the Company must estimate the net present value of cash flows expected to be collected. If the amortized cost exceeds the net present value of cash flows, such excess is considered a credit loss and an other-than-temporary impairment has occurred. For securities that are deemed other-than-temporarily impaired (“OTTI”), the amount of impairment is recognized in the statement of operations and is limited to the amount related to credit losses, while impairment related to other factors is recognized in other comprehensive income (loss). The Company did not recognize OTTI on its marketable securities during the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015.

Restricted cash:

Restricted cash is primarily invested in short-term bank deposits, which are primarily used to guarantee a letter of credit which has been issued to one of the Company’s major vendors, to the Company’s landlords for its office leases, and as security for the Company’s credit cards.

Inventories:

Inventories are stated at the lower of cost or market value. Inventory reserves are provided to cover risks arising from slow-moving items or technological obsolescence.

The Company periodically evaluates the quantities on hand relative to historical, current, and projected sales volume. Based on this evaluation, an impairment charge is recorded when required to write-down inventory to its market value. Cost of finished goods and raw materials is determined using the moving average cost method.

Property, equipment, and intangible assets:

Property and equipment:

Property and equipment are stated at cost, net of accumulated depreciation. Machinery & equipment in progress is the construction or development of property and equipment that have not yet been placed in service for the Company's intended use. Depreciation is calculated by the straight-line method over the estimated useful lives of the assets, at the following rates:

		%

Computers and peripheral equipment		15 – 33 (mainly 33)
Office furniture and equipment		7
Machinery & equipment		7 – 20 (mainly 10)
Laboratory equipment		15 – 25 (mainly 15)
Vehicles		15
Leasehold improvements		over the shorter of the lease term or useful economic life

Intangible assets:

Intangible assets are stated at cost, net of accumulated amortization. Amortization is calculated by the straight-line method over the estimated useful lives of the assets (see Note 7).

Impairment of long-lived assets:

The Company’s long-lived assets are reviewed for impairment in accordance with ASC 360 (“Property, Plants and Equipment”), whenever events or changes in circumstances indicate that the carrying amount of an asset (or asset group) may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset (or asset group) to the future undiscounted cash flows expected to be generated by the assets (or asset group).

If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds their fair value. For the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015, no impairment losses have been identified.

k. Severance pay:

Pursuant to Israel’s Severance Pay Law, Israeli employees are entitled to severance pay equal to one month’s salary for each year of employment, or a portion thereof. The employees of the Company’s Israeli subsidiary have elected to be included under section 14 of the Severance Pay Law, 1963, under which these employees are entitled only to monthly deposits made in their name with insurance companies, at a rate of 8.33% of their monthly salary. These payments cause the Company to be released from any future obligation under the Israeli Severance Pay Law to make severance payments in respect of those employees; therefore, related assets and liabilities are not presented in the balance sheet.

For the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015, the Company recorded $2,995, $1,131, $1,761, and $1,273 in severance expenses, respectively.

Revenue recognition:

The Company and its subsidiaries generate their revenues mainly from the sale of power optimizers, inverters, and cloud-based monitoring services to distributors, installers and PV module manufacturers.

Revenues from product sales and related services are recognized in accordance with ASC 605 (“Revenue Recognition”) when persuasive evidence of an arrangement exists, delivery has occurred, the selling price is fixed or determinable, collectability is reasonably assured, and no significant obligations remain.

Persuasive evidence of an arrangement exists. The Company’s customers mainly consist of distributors and installers (the “Customers”). The Company’s sales arrangements with Customers are pursuant to written documentation, either by a written contract or purchase order. The actual documentation used is dependent on the business practice with each Customer. Therefore, the Company determines that persuasive evidence of an arrangement exists with respect to a Customer when it has a written contract or a binding purchase order from the Customer.

Delivery has occurred. Each item of written documentation relating to a sale arrangement that is agreed upon with the Customer specifically sets forth when risk of loss and title are being transferred (based on the agreed International Commercial terms, or “INCOTERMS”). Unless a different written arrangement with the Customer exists, the Company determines that risk of loss and title are transferred to the Customer when the applicable INCOTERMS are satisfied and thus delivery of its products has occurred.

The fee is fixed or determinable. The Company does not provide any price protection, stock rotation, and/or right of return, and thus the Company considers all the Customers as end-users and the fee is considered fixed and determinable upon execution of the written documentation with the Customers.

Additionally, payments that are due within the normal course of the Company’s credit terms, which are currently no more than three months from the delivery date, are deemed to be fixed and determinable. Fees and arrangements with payment terms extending beyond customary payment terms are considered not to be fixed or determinable, in which case revenues are deferred and recognized when payments become due, provided that all other revenue recognition criteria have been met.

Collectability is reasonably assured. The Company determines whether collectability is reasonably assured on a Customer-by-Customer basis pursuant to its credit review policy. The Company typically sells to Customers with whom it has a long-term business relationship and a history of successful collection. For a new Customer, or when an existing Customer substantially expands its commitments, the Company evaluates the Customer’s financial position, the number of years the Customer has been in business, the history of collection with the Customer, and the Customer’s ability to pay, and typically assigns a credit limit based on that review.

Provisions for rebates, sales incentives, and discounts to customers are accounted for as reductions in revenue in the same period the related sales are recorded.

The Company increases a credit limit only after it has established a successful collection history with the Customer. The Company recognizes revenue under a particular arrangement as Customer payments are actually received if it determines at any time that collectability is not reasonably assured under that arrangement based upon its credit review process, the Customer’s payment history, or information that comes to light about a Customer’s financial position. No material revenues were recognized by the Company under that arrangement.

Revenues related to cloud-based monitoring and communication services are recognized ratably on a straight-line basis over the estimated service period.

For multiple-element arrangements, the Company allocates revenue to all deliverables based on their relative selling prices. In such circumstances, the Company uses a hierarchy to determine the selling price to be used for allocating revenue to deliverables: (i) vendor-specific objective evidence of fair value (“VSOE”), (ii) third-party evidence of selling price (“TPE”), and (iii) best estimate of the selling price (“ESP”).

VSOE generally exists only when the Company sells the deliverable separately and is the price actually charged by the Company for that deliverable. ESPs reflect the Company’s best estimates of what the selling prices of elements would be if they were sold regularly on a stand-alone basis. The Company has allocated revenue between its deliverables based on their relative selling prices. Because the Company has neither VSOE nor TPE for its deliverables, the allocation of revenue has been based on the Company’s ESPs. Amounts allocated to the delivered elements are recognized at the time of sale provided the other conditions for revenue recognition have been met.

The Company’s process for determining its ESP considers multiple factors that may vary depending upon the unique facts and circumstances related to each deliverable.

Key factors considered by the Company in developing the ESPs for its products include prices charged by the Company for similar offerings, the Company’s historical pricing practices and product-specific business objectives.

Deferred revenues consist of deferred cloud-based monitoring services, communication services and advance payments received from Customers for the Company’s products, and warranty extensions services, and are classified as short-term and long-term deferred revenues based on the period in which revenues are expected to be recognized.

Cost of revenues:

Cost of revenues sold includes the following: product costs consisting of purchases from contract manufacturers and other suppliers, indirect manufacturing costs, shipping and handling costs, support, warranty expenses and changes in warranty provision, provision for losses related to slow moving and dead inventory, personnel and logistics costs, and royalty expense payments to the Israel Innovation Authority (“IIA”) (see Note 2p).

Shipping and handling costs:

Shipping and handling costs, which amounted to $29,693, $8,131, $21,922, and $26,931 for the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015, respectively, are included in cost of revenues in the consolidated statements of operations. Shipping and handling costs include all costs associated with the distribution of finished products from the Company’s point of selling directly to its Customers.

Warranty obligations:

The Company’s products include a 10-year limited warranty for StorEdge products, a minimum 12-year limited warranty for inverters, and a 25-year limited warranty for power optimizers. In certain cases, the Company provides extended warranties for inverters that bring the warranty period up to 25 years. The Company maintains reserves to cover the expected costs that could result from these warranties. The warranty liability is generally in the form of product replacement and associated costs. Warranty reserves are based on the Company’s best estimate of such costs and are included in cost of revenues. The reserve for the related warranty expenses is based on various factors including assumptions about the frequency of warranty claims on product failures, derived from results of accelerated lab testing, field monitoring, analysis of the history of product field failures, and the Company’s reliability estimates.

The Company has established a reliability measurement system based on the units’ estimated mean time between failure, or MTBF, a metric that equates to a steady-state failure rate per year for each product generation. The MTBF predicts the expected failure rate of each product within the Company's products installed base during the expected product warranted lifetime.

The Company performs accelerated life cycle testing, which simulates the service life of the product in a short period of time.

The accelerated life cycle tests incorporate test methodologies derived from standard tests used by solar module vendors to evaluate the period over which solar modules wear out. Corresponding replacement costs are updated periodically to reflect changes in the Company’s actual and estimated production costs for its products, rate of usage of refurbished units as a replacement of faulty units, and other costs related to logistic and subcontractors services associated with the replacement.

In addition, through the collection of actual field failure statistics, the Company has identified several additional failure causes that are not included in the MTBF calculations. Such causes, which mostly consist of design errors, workmanship errors caused during the manufacturing process and, to a lesser extent, replacement of non-faulty units by installers, are generating additional replacement costs to the replacement costs projected under the MTBF model. The Company identified each of those causes, its failure pattern and the relative ratio compared to the pattern of malfunctions identified under the MTBF and accrued additional provisions for the occurrence of such malfunctioning. For the major causes of failures, the Company evaluates the continuation of these occurrences and the appearance of potential additional malfunctioning cases beyond the MTBF pattern and accrues additional expenses accordingly.

Warranty obligations are classified as short-term and long-term obligations based on the period in which the warranty is expected to be claimed.

Government grants:

Government grants received by the Company’s Israeli subsidiary relating to categories of operating expenditures are credited to the consolidated statements of operations during the period in which the expenditure to which they relate is charged. Royalty-bearing grants from the IIA for funding certain approved research and development projects are recognized at the time when the Company’s Israeli subsidiary is entitled to such grants, on the basis of the related costs incurred, and are included as a deduction from research and development expenses.

The Company recorded grants in the amount of $763 for the year ended June 30, 2015, which was deducted from research and development expenses.

No grants were recorded for the year ended December 31, 2017, the six months ended December 31, 2016, and for the year ended June 30, 2016.

Research and development costs:

Research and development costs, net of grants received, are charged to the consolidated statement of operations as incurred.

Concentrations of credit risks:

Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents, restricted cash, trade receivables, other accounts receivable, and marketable securities.

Cash and cash equivalents are mainly invested in major banks in the U.S., Israel, Australia, Japan, and Germany. Management believes that the financial institutions that hold the Company’s investments are financially sound and, accordingly, minimal credit risk exists with respect to these investments.

The Company’s marketable securities consist of corporate and governmental bonds.

The Company's marketable securities include investments in highly-rated corporate debentures (mainly of U.S., UK, France, Canada, and other countries) and governmental bonds. The financial institutions that hold the Company's marketable securities are major financial institutions located in the United States. Management believes that the Company's marketable securities portfolio is a diverse portfolio of highly-rated securities and the Company's investment policy limits the amount the Company may invest in each issuer, and accordingly, management believes that minimal credit risk exists from geographic or credit concentration with respect to these securities.

As of December 31, 2017, December 31, 2016, and June 30, 2016, the amortized cost of the Company’s marketable securities was $180,974, $118,950, and $111,514, respectively, and their stated market value was $180,384, $118,727, and $111,609, respectively, representing a net unrealized loss of $590, $223, and a net unrealized gain of $95, respectively.

The trade receivables of the Company are derived from sales to Customers located primarily in North America, Europe, and Australia.

The Company generally does not require collateral, however, in certain circumstances, the Company may require letters of credit, other collateral, or additional guarantees.

An allowance for doubtful accounts is determined with respect to specific debts that are doubtful of collection. The Company accrued $128, $226, and $235 as allowance for doubtful accounts as of December 31, 2017 and 2016 and June 30, 2016, respectively.

In addition, an accrual for rebates is allocated to specific debts. The Company accrued $17,428, $9,089, and $4,294 for rebates as of December 31, 2017 and 2016 and June 30, 2016, respectively.

As of December 31, 2017 and 2016 and June 30, 2016, the Company had two, one, and two major customers (customers with a balance that represents more than 10% of total trade receivables), respectively, which accounted in the aggregate for approximately 35.2%, 20.2%, and 34.4%, respectively, of the Company’s consolidated trade receivables.

The Company and its subsidiaries have no off-balance sheet concentration of credit risk except for certain derivative instruments as mentioned below.

s. Fair value of financial instruments:

The following methods and assumptions were used by the Company in estimating the fair value of its financial instruments:

The carrying value of cash and cash equivalents, restricted cash, trade receivables, prepaid expenses and other accounts receivable, trade payables, employee and payroll accruals and accrued expenses, and other accounts payable approximate their fair values due to the short-term maturities of such instruments.

Assets measured at fair value on a recurring basis as of December 31, 2017, December 31, 2016, and June 30, 2016 are comprised of money market funds, foreign currency derivative contracts and marketable securities. (see Note 4)

The Company applies ASC 820 (“Fair Value Measurements and Disclosures”), with respect to fair value measurements of all financial assets and liabilities.

Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability.

A three-tiered fair value hierarchy is established as a basis for considering such assumptions and for inputs used in the valuation methodologies in measuring fair value:

Level 1-

Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets.

Level 2-

Include other inputs that are directly or indirectly observable in the marketplace.

Level 3-

Unobservable inputs which are supported by little or no market activity.

The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value.

Warrants to Purchase Convertible Preferred Stock:

The Company accounts for freestanding warrants to purchase shares of its convertible preferred stock as a liability on the balance sheets at fair value. The warrants to purchase convertible preferred stock are recorded as a liability because of a provision calling for minimum proceeds upon or after an “Exit Event”, as described in Note 10.

The fair value of warrants to purchase convertible preferred stock on the issuance date and on subsequent reporting dates was determined using a hybrid method utilizing the assumptions noted below. The fair value of the underlying preferred stock price was determined by the board of directors considering, among others, third party valuations. The valuation of the Company was performed using the hybrid method, a hybrid between the probability-weighted estimated return method (“PWERM”) and Option Pricing Method (“OPM”) estimating the probability-weighted value across multiple scenarios but using the OPM to estimate the allocation of value within one or more of those scenarios. The OPM was used to allocate the Company’s equity value between the preferred stock, common stock and warrants in a scenario of other liquidation events.

The expected terms of the warrants were based on the remaining contractual expiration period. The expected share price volatility for the shares was determined by examining the historical volatilities of a group of the Company’s industry peers as there was insufficient trading history of the Company’s shares. The risk-free interest rate was calculated using the average of the published interest rates for U.S. Treasury zero-coupon issues with maturities that approximate the expected term.

The dividend yield assumption was zero, as there is no history of dividend payments and the Company does not expect to pay any dividends in the foreseeable future.

The following assumptions were used to estimate the value of the warrants to purchase convertible preferred stock:

	June 30,
	2014

Expected volatility		45.0	%
Risk-free rate		0.09	%
Dividend yield		0	%
Expected term (in years)		1.21

The warrants to purchase convertible preferred stock were subject to re-measurement to fair value at each balance sheet date and any change in fair value was recognized as a component of financial expenses, net, on the statements of operations.

The change in the fair value of warrants to purchase convertible preferred stock is summarized below:

	Balance at beginning of period		Issuance of warrants to purchase preferred stock		Exercise of warrants to purchase common stock (*)			Change in fair value		Balance at end of period

June 30, 2015	$	765	$	-	$	(6,115	)	$	5,350	$	-

(*)

Upon the closing of the IPO, all outstanding warrants to purchase convertible preferred stock automatically converted into warrants to purchase 187,671 shares of common stock (See Note 1c).

On June 18, 2015, the warrants were redeemed in a cashless exercise into 154,768 common shares. Immediately before the cashless exercise, the warrants were remeasured to fair value based on their intrinsic value which amounted to $6,115 (see Note 10).

Accounting for stock-based compensation:

The Company accounts for stock-based compensation in accordance with ASC 718 (“Compensation-Stock Compensation”). ASC 718 requires companies to estimate the fair value of equity-based payment awards on the date of grant using an Option-Pricing Model (“OPM”). The value of the portion of the award that is ultimately expected to vest is recognized as an expense over the requisite service periods in the Company’s consolidated statements of operations.

The Company recognizes compensation expenses for the value of its awards granted based on the straight-line method over the requisite service period of each of the awards, net of estimated forfeitures. ASC 718 requires forfeitures to be estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Estimated forfeitures are based on actual historical pre-vesting forfeitures (pursuant to the adoption of ASU 2016-09, the Company made a policy election to estimate the number of awards that are expected to vest).

The Company selected the Black-Scholes-Merton option pricing model as the most appropriate fair value method for its stock-option awards and Employee Stock Purchase Plan. The option-pricing model requires a number of assumptions, of which the most significant are the fair market value of the underlying common stock, expected stock price volatility, and the expected option term. Expected volatility for stock-option awards was calculated based upon certain peer companies that the Company considered to be comparable. Expected volatility for Employee Stock Purchase Plan was calculated based upon the Company’s stock prices. The expected option term represents the period of time that options granted are expected to be outstanding. The expected option term is determined based on the simplified method in accordance with SAB No. 110, as adequate historical experience is not available to provide a reasonable estimate. The simplified method will continue to apply until enough historical experience is available to provide a reasonable estimate of the expected term. The risk-free interest rate is based on the yield from U.S. treasury bonds with an equivalent term. The Company has not declared or paid any dividends on its common stock and does not expect to pay any dividends in the foreseeable future.

The fair value for options granted to employees and executive directors and Employee Stock Purchase Plan in the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015 is estimated at the date of grant using a Black-Scholes-Merton option pricing model with the following assumptions:

	Year ended December 31, 2017			Six months ended December 31, 2016			Year Ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016			2016			2015
Employee Stock Options
Risk-free interest		2.14% - 2.17	%		1.28% - 1.34	%		1.39% - 1.97	%		1.39% - 2.06	%
Dividend yields		0	%		0	%		0	%		0	%
Volatility		58.08% - 58.10	%		55.33% - 55.34	%		55.45%-56.03	%		46.5%-55.1	%
Expected option term in years		6.06			6.06			5.50-6.11			5.50-6.27
Estimated forfeiture rate		0	%		0	%		10.3	%		12.5%-18.7	%
Employee Stock Purchase Plan
Risk-free interest		0.6% - 1.07	%		0.60	%		0.40	%		-
Dividend yields		0	%		0	%		0	%		-
Volatility		45.6% - 48.08	%		48.08	%		62.84	%		-
Expected term	6 months			6 months			6 months				-

The following table set forth the parameters used in computation of the options compensation to non-employee consultants in the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015, using a Black-Scholes-Merton option pricing model with the following assumptions:

	Year ended December 31, 2017			Six months ended December 31, 2016			Year ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016			2016			2015

Risk-free interest		2.12% - 2.42	%		1.16% - 2.45	%		1.15%-2.21	%		1.59%-2.58	%
Dividend yields		0	%		0	%		0	%		0	%
Volatility		61.21% - 62.62	%		55.33% - 58.57	%		55.37%-55.75	%		45.5%-56.2	%
Contractual life in years		6-10			6 - 10			6.4-10			7.4-10

The Company recognizes compensation expenses for the value of its restricted stock unit (“RSU”) awards, based on the straight-line method over the requisite service period of each of the awards, net of estimated forfeitures. The fair value of each RSU is the market value as determined by the closing price of the common stock on the day of grant.

Income taxes:

The Company and its subsidiaries account for income taxes in accordance with ASC 740, “Income Taxes.” ASC 740 prescribes the use of the liability method, whereby deferred tax asset and liability account balances are determined based on differences between financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates that will be in effect when the differences are expected to reverse.

The Company accounts for uncertain tax positions in accordance with ASC 740. ASC 740-10 contains a two-step approach to recognizing and measuring uncertain tax positions. The first step is to evaluate the tax position taken or expected to be taken in a tax return by determining if the weight of available evidence indicates that it is more likely than not that, on an evaluation of the technical merits, the tax position will be sustained on audit, including resolution of any related appeals or litigation processes. The second step is to measure the tax benefit as the largest amount that is more than 50% (cumulative probability) likely to be realized upon ultimate settlement.

The Company record reserves for uncertain tax positions to the extent it is more likely than not that the tax position will be sustained on audit, based on the technical merits of the position.

Derivative financial instruments:

The Company accounts for derivatives and hedging based on ASC 815 (“Derivatives and Hedging”). ASC 815 requires the Company to recognize all derivatives on the balance sheet at fair value. The accounting for changes in the fair value (i.e., gains or losses) of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and further, on the type of hedging relationship.

To protect against the increase in value of forecasted foreign currency cash flows resulting from salary and lease payments of its Israeli facilities denominated in the Israeli currency, the New Israeli Shekel (“NIS”), the Company instituted a foreign currency cash flow hedging program. The Company hedges portions of the anticipated payroll and lease payments denominated in NIS for a period of one to twelve months with hedging contracts. These hedging contracts are designated as cash flow hedges, as defined by ASC 815 and are all effective hedges.

In accordance with ASC 815, for derivative instruments that are designated and qualify as a cash flow hedge (i.e. hedging the exposure to variability in expected future cash flows that is attributable to a particular risk), the effective portion of the gain or loss on the derivative instrument is reported as a component of other comprehensive income and reclassified into earnings in the same period or periods during which the hedged transaction affects earnings. Any gain or loss on a derivative instrument in excess of the cumulative change in the present value of future cash flows of the hedged item is recognized in current earnings during the period of change.

In addition to the above-mentioned cash flow hedges transactions, the Company also entered into derivative instrument arrangements to hedge the Company’s exposure to currencies other than the U.S. dollar. These derivative instruments are not designated as cash flow hedges, as defined by ASC 815, and therefore all gains and losses, resulting from fair value remeasurement, were recorded immediately in the statement of operations, as financial income (expenses).

As of December 31, 2017, the Company entered into forward contracts and put and call options to sell Euros for U.S. dollars in the amount of €54 million.

As of December 31, 2017, the Company had no derivative instruments that are designated as cash flow hedges.

As of December 31, 2016, the Company entered into forward contracts to sell U.S. dollars for NIS in the amount of $5,098. These hedging contracts do not contain any credit-risk-related contingency features. See Note 4 for information on the fair value of these hedging contracts.

As of December 31, 2016, the Company had no derivative instruments that are not designated as cash flow hedges.

As of June 30, 2016, the Company entered into forward contracts and put and call options to sell U.S. dollars for NIS and Euros for U.S. dollars in the amount of $17,693 and €30 million, respectively. These hedging contracts do not contain any credit-risk-related contingency features.

The fair value of derivative assets and derivative liabilities as of December 31, 2017 was $221 and $401, respectively, which was recorded at net amount in accrued expenses and other accounts payable in the consolidated balance sheets (see Note 13).

The fair value of derivative assets as of December 31, 2016 was $19, which was recorded in other accounts receivable and prepaid expenses in the consolidated balance sheets (see Note 13).

The fair value of derivative assets and derivative liabilities as of June 30, 2016 was $504 and $23, respectively, which was recorded at net amount in other accounts receivable and prepaid expenses in the consolidated balance sheets.

The Company recorded changes in the fair value (i.e., gains or losses) of the derivatives in the accompanying consolidated statements of cash flows as changes in operating activities.

Comprehensive income:

The Company reports comprehensive income in accordance with ASC 220 (“Comprehensive Income”). ASC 220 establishes standards for the reporting and presentation of comprehensive income and its components in a full set of general purpose financial statements.

Total comprehensive income and the components of accumulated other comprehensive income are presented in the consolidated statements of stockholders’ equity. Accumulated other comprehensive income consists of foreign currency translation effects, unrealized gains and losses on available-for-sale marketable securities and hedging contracts.

New accounting pronouncements not yet effective:

In May 2014, the FASB issued a new standard related to revenue recognition. Under the new standard, revenue is recognized when a customer obtains control of promised goods or services and is recognized in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. In addition, the standard requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flow arising from contracts with customers. The guidance permits two methods of modification: retrospectively to each prior reporting period presented (full retrospective method), or retrospectively with the cumulative effect of initially applying the guidance recognized at the date of initial application (the modified retrospective method.). The Company will adopt the new standard, effective January 1, 2018, using the modified retrospective method applied to those contracts which were not substantially completed as of January 1, 2018. The cumulative adjustment will decrease the Company’s retained earnings by $3,875 while increasing the Company’s deferred revenues by the same amount.

The most significant impact of the standard on the Company’s financial statements relates to advance payments received for performance obligations that extend for a period greater than one year. Applying the new standard, such performance obligations related to warranty extension services, cloud-based monitoring, and other communication services are those that include a financial component.

Upon adoption, the financing component will result in interest expenses which will be included in the Company’s consolidated statement of operations to reflect the financial portion cost of the long-term deferred revenue that is related to such services.

In February 2016, the FASB issued ASU 2016-02, “Leases” (Topic 842), whereby lessees will be required to recognize for all leases at the commencement date a lease liability, which is a lessee‘s obligation to make lease payments arising from a lease, measured on a discounted basis, and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. Under the new guidance, lessor accounting is largely unchanged. A modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements must be applied. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented. Companies may not apply a full retrospective transition approach. ASU 2016-02 is effective for annual and interim periods beginning after December 15, 2018. Early application is permitted. The Company is evaluating the potential impact of this pronouncement.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. ASU 2016-13 amends the impairment model to utilize an expected loss methodology in place of the currently used incurred loss methodology, which will result in the more timely recognition of losses. ASU 2016-13 also applies to employee benefit plan accounting, with an effective date of the first quarter of fiscal 2022. The Company is currently assessing the impact that adopting this new accounting standard will have on its consolidated financial statements, footnote disclosures, and employee benefit plans’ accounting.

In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, which provides guidance with the intent of reducing diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. ASU No. 2016-15 is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years with early adoption permitted, including adoption in an interim period. The Company will adopt the new standard effective January 1, 2018, and does not expect the adoption of this guidance to have a material impact on the Company’s consolidated financial statements.

In October 2016, the FASB issued Accounting Standards Update No. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers Other than Inventory (ASU 2016-16), which requires companies to recognize the income-tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs, rather than when the asset has been sold to an outside party. The Company will adopt the new standard effective January 1, 2018 and does not expect the adoption of this guidance to have a material impact on the Company’s consolidated financial statements.

In November 2016, the FASB issued Accounting Standards Update No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (ASU 2016-18), which requires companies to include amounts generally described as restricted cash and restricted cash equivalents in cash and cash equivalents when reconciling beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The Company will adopt the new standard effective January 1, 2018, and does not expect the adoption of this guidance to have a material impact on the Company’s consolidated financial statements.

In May 2017, the FASB issued ASU 2017-09, "Compensation – Stock Compensation (Topic 718): Scope of Modification Accounting." ASU 2017-09 was issued to provide clarity and reduce both 1) diversity in practice and 2) cost and complexity when applying the guidance in Topic 718 to a change in the terms or conditions of a share-based payment award. ASU 2017-09 provides guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting under Topic 718. The amendments in ASU 2017-09 are effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. Early adoption is permitted, including adoption in any interim period. The amendments in ASU 2017-09 should be applied prospectively to an award modified on or after the adoption date. The Company will adopt the new standard effective January 1, 2018 and adoption of this standard is not expected to have a material impact on the consolidated financial statements.

In January 2018, the FASB released guidance on the accounting for tax on the global intangible low-taxed income ("GILTI") provisions of the Tax Cuts and Jobs Act (the "TCJA"). The GILTI provisions impose a tax on foreign income in excess of a deemed return on tangible assets of foreign corporations. The guidance indicates that either accounting for deferred taxes related to GILTI inclusions or to treat any taxes on GILTI inclusions as period cost are both acceptable methods subject to an accounting policy election. Due to the complexity of this new tax rule, the Company continues to evaluate this provision of the TCJA and whether such taxes are recorded as a current-period expense when incurred or whether such amount should be factored into a company’s measurement of its deferred taxes. As a result, the Company has not included an estimate of the tax expense/benefit related to this item for the year ended December 31, 2017.

aa.

Recently issued and adopted pronouncements:

In July 2015, the FASB issued ASU No. 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory (“ASU 2015-11”). The new standard applies only to inventory for which cost is determined by methods other than last-in, first-out or the retail inventory method, such as inventory measured using first-in, first-out, or average cost. Inventory within the scope of ASU 2015-11 is required to be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The Company adopted ASU 2015-11 during the first quarter of 2017, which did not have a material impact on our results of operations, cash flows, or financial position.

MARKETABLE SECURITIES

12 Months Ended

Dec. 31, 2017

Marketable Securities [Abstract]

MARKETABLE SECURITIES

NOTE 3:-

MARKETABLE SECURITIES

The following is a summary of available-for-sale marketable securities at December 31, 2017:

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value

Available for-sale – matures within one year:
Corporate bonds	$	68,392	$	1	$	(121	)	$	68,272
Governmental bonds		9,019		-		(27	)		8,992
		77,411		1		(148	)		77,264

Available for-sale – matures after one year:
Corporate bonds		95,540		-		(380	)		95,160
Governmental bonds		8,023		-		(63	)		7,960
		103,563		-		(443	)		103,120

Total	$	180,974	$	1	$	(591	)	$	180,384

The following is a summary of available-for-sale marketable securities at December 31, 2016:

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value

Available for-sale – matures within one year:
Corporate bonds	$	71,753	$	20	$	(54	)	$	71,719
Governmental bonds		2,758		-		(12	)		2,746
		74,511		20		(66	)		74,465

Available for-sale – matures after one year:
Corporate bonds		39,435		3		(159	)		39,279
Governmental bonds		5,004		-		(21	)		4,983
		44,439		3		(180	)		44,262

Total	$	118,950	$	23	$	(246	)	$	118,727

The following is a summary of available-for-sale marketable securities at June 30, 2016:

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value

Available for-sale – matures within one year:
Corporate bonds	$	57,119	$	50	$	(11	)	$	57,158
Governmental bonds		2,005		-		-			2,005
		59,124		50		(11	)		59,163

Available for-sale – matures after one year:
Corporate bonds		46,375		86		(31	)		46,430
Governmental bonds		6,015		7		(6	)		6,016
		52,390		93		(37	)		52,446

Total	$	111,514	$	143	$	(48	)	$	111,609

The following table presents gross unrealized losses and fair values for those investments that were in an unrealized loss position as of December 31, 2017, December 31, 2016, and June 30, 2016 based on the investments maturity date:

	Less than 12 months					12 months or greater
	Fair value		Gross unrealized losses			Fair value		Gross unrealized losses

As of December 31, 2017	$	72,269	$	(148	)	$	103,116	$	(443	)
As of December 31, 2016	$	51,124	$	(66	)	$	39,373	$	(180	)
As of June 30, 2016	$	22,895	$	(11	)	$	20,070	$	(37	)

As of December 31, 2017 and 2016 and June 30, 2016, management believes the unrealized losses are not other than temporary and therefore such unrealized losses were recorded in accumulated other comprehensive income (loss). The Company has no intent to sell these securities and it is more likely than not that the Company will not be required to sell these securities prior to the recovery of the entire amortized cost basis.

Proceeds from maturity of available-for-sale marketable securities during the year ended December 31, 2017, the six months ended December 31, 2016, and the year ended June 30, 2016 were $80,269, $32,782 and $6,350, respectively. The Company had no proceeds from sales of available-for-sale marketable securities during the year ended December 31, 2017, the six months ended December 31, 2016, and the year ended June 30, 2016, therefore no realized gains or losses from the sale of available-for sale marketable securities were recognized. The Company determines realized gains or losses on the sale of available-for-sale marketable securities based on a specific identification method.

FAIR VALUE MEASUREMENTS

12 Months Ended

Dec. 31, 2017

Fair Value Measurements

FAIR VALUE MEASUREMENTS

NOTE 4:-

FAIR VALUE MEASUREMENTS

In accordance with ASC 820, the Company measures its cash equivalents, foreign currency derivative contracts, and marketable securities, at fair value using the market approach valuation technique. Cash equivalents and marketable securities are classified within Level 1 or Level 2. This is because these assets are valued using quoted market prices or alternative pricing sources and models utilizing market observable inputs. Foreign currency derivative contracts are classified within the Level 2 value hierarchy, as the valuation inputs are based on quoted prices and market observable data of similar instruments.

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2017 by level within the fair value hierarchy:

	Balance as of			Fair value measurements
Description	December 31, 2017			Level 1		Level 2			Level 3

Cash equivalents:
Money market mutual funds	$	6,163		$	6,163		-			-

Derivative instruments liability	$	(180	)		-	$	(180	)		-

Short-term marketable securities:
Corporate bonds	$	68,272			-	$	68,272			-
Governmental bonds	$	8,992			-	$	8,992			-

Long-term marketable securities:
Corporate bonds	$	95,160			-	$	95,160			-
Governmental bonds	$	7,960			-	$	7,960			-

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2016 by level within the fair value hierarchy:

	Balance as of		Fair value measurements
Description	December 31, 2016		Level 1		Level 2		Level 3

Cash equivalents:
Money market mutual funds	$	6,510	$	6,510		-		-

Derivative instruments asset	$	19		-	$	19		-

Short-term marketable securities:
Corporate bonds	$	71,719		-	$	71,719		-
Governmental bonds	$	2,746		-	$	2,746		-

Long-term marketable securities:
Corporate bonds	$	39,279		-	$	39,279		-
Governmental bonds	$	4,983		-	$	4,983		-

The following table sets forth the Company’s assets that were measured at fair value as of June 30, 2016 by level within the fair value hierarchy:

	Balance as of		Fair value measurements
Description	June 30, 2016		Level 1		Level 2		Level 3

Cash equivalents:
Money market mutual funds	$	13,373	$	13,373		-		-

Derivative instruments asset	$	481		-	$	481		-

Short-term marketable securities:
Corporate bonds	$	57,158		-	$	57,158		-
Governmental bonds	$	2,005		-	$	2,005		-

Long-term marketable securities:
Corporate bonds	$	46,430		-	$	46,430		-
Governmental bonds	$	6,016		-	$	6,016		-

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

PREPAID EXPENSES AND OTHER ACCOUNTS RECEIVABLE

12 Months Ended

Dec. 31, 2017

PREPAID EXPENSES AND OTHER ACCOUNTS RECEIVABLE

NOTE 5:-

PREPAID EXPENSES AND OTHER ACCOUNTS RECEIVABLE

	December 31,				June 30,
	2017		2016		2016

Vendor non-trade receivables (*)	$	33,719	$	15,209	$	15,375
Government authorities		3,421		2,585		2,727
Prepaid expenses and other		5,083		3,534		2,756
Foreign currency derivative contracts		-		19		482

	$	42,223	$	21,347	$	21,340

(*) Vendor non-trade receivables related to contract manufacturers derive from the sale of components to manufacturing vendors who manufacture products for the Company. The Company purchases these components directly from other suppliers. The Company does not reflect the sale of these components to the contract manufacturers in revenues (see also Note 14e).

INVENTORIES

12 Months Ended

Dec. 31, 2017

Inventory Disclosure [Abstract]

INVENTORIES

NOTE 6:-

INVENTORIES

	December 31,				June 30,
	2017		2016		2016

Raw materials	$	25,887	$	10,053	$	9,805
Finished goods		57,105		57,310		71,745

	$	82,992	$	67,363	$	81,550

The Company recorded inventory write-downs of $1,352, $113, $2,539, and $992 for the year ended December 31, 2017, the six months ended December 31, 2016, and for the years ended June 30, 2016 and 2015, respectively.

PROPERTY AND EQUIPMENT AND INTANGIBLE ASSETS, NET

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

PROPERTY AND EQUIPMENT AND INTANGIBLE ASSETS, NET

NOTE 7:-

PROPERTY AND EQUIPMENT AND INTANGIBLE ASSETS, NET

Property and equipment:

	As of December 31,				As of June 30,
	2017		2016		2016

Cost:

Computers and peripheral equipment	$	9,872	$	6,053	$	5,190
Office furniture and equipment		1,785		1,505		1,289
Laboratory and testing equipment		13,732		9,589		8,590
Machinery and equipment		38,422		26,285		18,433
Leasehold improvements		7,536		5,898		5,450
Vehicles		39		13		13

		71,386		49,343		38,965

Less - accumulated depreciation		20,204		13,221		11,134

Depreciated cost	$	51,182	$	36,122	$	27,831

Property in progress under construction and development with a cost basis of $8,783, $10,698, and $5,519 was included in Machinery and equipment as of December 31, 2017 and 2016 and June 30, 2016, respectively.

Depreciation expenses for the year ended December 31, 2017, the six months ended December 31, 2016, and for the years ended June 30, 2016 and 2015 were $7,011, $2,702, $3,763, and $2,253, respectively.

Intangible assets:

On March 9, 2015, the Company and Beacon Power LLC, a Delaware limited liability company (“Beacon”) entered into a patent purchase agreement pursuant to which the Company agreed to purchase all rights in the patents. In July 2015, the Company completed the purchase of the patents for $800.

In October 2016, the Company and Accurate Solar Power, LLC, a limited liability corporation, entered into a patent purchase agreement, under which the Company agreed to purchase certain patents, provisional patent applications, and pending patent applications. The Company completed the purchase in return for total consideration of $600.

Intangible assets include an acquired patents with an original cost of $1,400 as of December 31, 2017 and December 31, 2016, and $800 as of June 30, 2016.

Accumulated amortization amounted to $285, $141, and $84 as of December 31, 2017, 2016 and June 30, 2016, respectively. The patents are amortized over a 10 year period.

Amortization expenses for the year ended December 31, 2017, for the six months ended December 31, 2016, and for the year ended June 30, 2016 were $144, $57, and $84, respectively.

ACCRUED EXPENSES AND OTHER ACCOUNTS PAYABLE

12 Months Ended

Dec. 31, 2017

Payables and Accruals [Abstract]

ACCRUED EXPENSES AND OTHER ACCOUNTS PAYABLE

NOTE 8:-

ACCRUED EXPENSES AND OTHER ACCOUNTS PAYABLE

	As of December 31,				As of June 30,
	2017		2016		2016

Accrued expenses	$	14,863	$	4,209	$	5,615
Government authorities		1,905		1,568		1,406
Loss provision related to contractual inventory purchase obligations *		1,627		2,009		2,834
Other		1,983		862		870

	$	20,378	$	8,648	$	10,725

See also Note 14e.

WARRANTY OBLIGATIONS

12 Months Ended

Dec. 31, 2017

Product Warranties Disclosures [Abstract]

WARRANTY OBLIGATIONS

NOTE 9:-

WARRANTY OBLIGATIONS

Changes in the Company’s product warranty liability for the year ended December 31, 2017, the six months ended December 31, 2016, and the year ended June 30, 2016 were as follows:

	December 31,						June 30,
	2017			2016			2016

Balance, at beginning of year	$	58,375		$	51,192		$	31,879
Additions and adjustments to cost of revenues		34,650			13,749			28,848
Usage and current warranty expenses		(14,214	)		(6,566	)		(9,535	)

Balance, at end of year		78,811			58,375			51,192
Less current portion		(14,785	)		(13,616	)		(14,114	)

Long term portion	$	64,026		$	44,759		$	37,078

TERM LOAN AND WARRANTS TO PURCHASE CONVERTIBLE PREFERRED STOCK

12 Months Ended

Dec. 31, 2017

Debt Instruments [Abstract]

TERM LOAN AND WARRANTS TO PURCHASE CONVERTIBLE PREFERRED STOCK

NOTE 10:-

TERM LOAN AND WARRANTS TO PURCHASE CONVERTIBLE PREFERRED STOCK

On December 28, 2012, (the “Agreement Date”), the Company entered into a loan facility agreement (the “Loan Agreement”) with a lender (the “Lender”), pursuant to which the Lender agreed to loan the Company up to $10,000. On the Agreement Date, the Company received a total of $10,000, less a $100 loan transaction fee paid to the Lender (the “Loan”). The Loan is for a period of 42 months and bears annual interest of 11.90%, which is to be paid monthly.

The principal of the loan is to be paid in 33 monthly payments, beginning in September 2013, except for the last loan payment which was paid in advance on the Agreement Date. Repayment of the Loan and payment of all other amounts owed to the Lender is paid in Euro.

In connection with the Loan Agreement, the Company granted the Lender 563,014 warrants to purchase Series D-1 convertible preferred stock at an exercise price of $2.309 (the “Warrants”). The Warrants were exercisable in whole or in part prior to earliest of (i) the tenth anniversary of the Agreement Date, or (ii) 12 months after a qualified initial public offering, or (iii) immediately prior to the consumption of a merger or sale of all or substantially all of the Company’s assets (“M&A Transaction”, and together with a qualified initial public offering, an “Exit Event”).

Upon the closing of the IPO, all outstanding warrants to purchase convertible preferred stock automatically converted into warrants to purchase 187,671 shares of common stock (See Note 1c).

In January 2015, the Company fully settled the amount borrowed from the Lender under the Term Loan.

On June 18, 2015, the Lender elected to exercise its cashless exercise rights under which the Company issued 154,768 shares of common stock. The fair value of the Warrants liability as of the exercise date in the amount of $6,115 was reclassified to stockholders’ equity (deficiency).

REVOLVING CREDIT LINE

12 Months Ended

Dec. 31, 2017

Line of Credit Facility [Abstract]

REVOLVING CREDIT LINE

NOTE 11:-

REVOLVING CREDIT LINE

In June 2011, the Company entered into an agreement for a revolving line of credit from a Bank Lender (the "Bank Lender"), which, as amended to date, permits aggregate borrowings of up to $20,000 in an amount not to exceed 80% of the eligible trade receivables plus 65% of inventories in transit to customers and bears interest, payable monthly, at the Bank Lender’s prime rate plus a margin of 0.75% to 2.75%.

On February 17, 2015, the Company amended and restated the agreement with the Bank Lender for a revolving line of credit, which permits aggregate borrowings of up to $40,000 in an amount not to exceed 80% of the eligible accounts receivable and bears interest, payable monthly, at the Bank Lender’s prime rate plus a margin of 0.5% to 2.0%. As of December 31, 2016, the revolving line of credit was terminated and the Company had no outstanding borrowings related to this revolving line of credit.

As of June 30, 2016 and 2015, the Company met all its Bank Lender covenants.

As of December 31, 2016, June 30, 2016 and 2015, the Company had no outstanding borrowings related to this revolving line of credit. The revolving line of credit terminated on December 31, 2016.

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)

12 Months Ended

Dec. 31, 2017

Accumulated Other Comprehensive Income Loss

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)

NOTE 12:- ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)

The following table summarizes the changes in accumulated balances of other comprehensive income, net of taxes, for the year ended December 31, 2017:

	Unrealized gains (losses) on available-for-sale marketable securities			Unrealized gains (losses) on cash flow hedges			Unrealized gains (losses) on foreign currency translation			Total

Beginning balance	$	(136	)	$	19		$	(207	)	$	(324	)
Other comprehensive income (loss) before reclassifications		(297	)		975			29			707
Gains reclassified from accumulated other comprehensive income		-			(994	)		-			(994	)
Net current period other comprehensive income (loss)		(297	)		(19	)		29			(287	)

Ending balance	$	(433	)	$	-		$	(178	)	$	(611	)

The following table summarizes the changes in accumulated balances of other comprehensive loss, net of taxes, for the six months ended December 31, 2016:

	Unrealized gains (losses) on available-for-sale marketable securities			Unrealized gains (losses) on cash flow hedges			Unrealized gains (losses) on foreign currency translation			Total

Beginning balance	$	57		$	243		$	(29	)	$	271
Other comprehensive income (loss) before reclassifications		(193	)		93			(178	)		(278	)
Gains reclassified from accumulated other comprehensive income		-			(317	)		-			(317	)
Net current period other comprehensive loss		(193	)		(224	)		(178	)		(595	)

Ending balance	$	(136	)	$	19		$	(207	)	$	(324	)

The following table summarizes the changes in accumulated balances of other comprehensive income, net of taxes, for the year ended June 30, 2016:

	Unrealized gains (losses) on available-for-sale marketable securities		Unrealized gains (losses) on cash flow hedges			Unrealized gains (losses) on foreign currency translation			Total

Beginning balance	$	-	$	-		$	(222	)	$	(222	)
Other comprehensive income (loss) before reclassifications		56		412			193			661
Losses (gains) reclassified from accumulated other comprehensive income (loss)		1		(169	)		-			(168	)
Net current period other comprehensive income		57		243			193			493

Ending balance	$	57	$	243		$	(29	)	$	271

The following tables provides details about reclassifications out of accumulated other comprehensive income (loss):

Details about Accumulated Other Comprehensive Loss Components	Amount Reclassified from Accumulated Other Comprehensive Loss		Affected Line Item in the Statements of Operations
	Year ended
	December 31, 2017

Unrealized gains on cash flow hedges	$	166	Cost of revenues
		570	Research and development
		151	Sales and marketing
		153	General and administrative

		1,040	Total, before income taxes

		46	Income tax expense

	$	994	Total, net of income taxes

Unrealized gains on available-for-sale marketable securities	$	-	Financial income, net
		-	Income tax expense

	$	-	Total, net of income taxes

	$	994	Total, net of income taxes

Details about Accumulated Other Comprehensive Loss Components	Amount Reclassified from Accumulated Other Comprehensive Loss		Affected Line Item in the Statements of Operations
	Six months ended
	December 31, 2016

Unrealized gains on cash flow hedges	$	47	Cost of revenues
		227	Research and development
		58	Sales and marketing
		46	General and administrative

		378	Total, before income taxes

		61	Income tax expense

	$	317	Total, net of income taxes

Unrealized gains on available-for-sale marketable securities	$	-	Financial income, net
		-	Income tax expense

	$	-	Total, net of income taxes

	$	317	Total, net of income taxes

Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Item in the Statements of Operations
	Year ended
	June 30, 2016

Unrealized gains on cash flow hedges	$	30		Cost of revenues
		115		Research and development
		33		Sales and marketing
		24		General and administrative

		202		Total, before income taxes

		33		Income tax expense

	$	169		Total, net of income taxes

Unrealized losses on available-for-sale marketable securities	$	(1	)	Financial income, net
		-		Income tax expense

	$	(1	)	Total, net of income taxes

	$	168		Total, net of income taxes

No amounts were reclassified from accumulated other comprehensive income for the year ended June 30, 2015.

DERIVATIVE INSTRUMENTS

12 Months Ended

Dec. 31, 2017

Derivative Instruments

DERIVATIVE INSTRUMENTS

NOTE 13:- DERIVATIVE INSTRUMENTS

The fair value of the Company’s outstanding derivative instruments is as follows:

	As of December 31,					As of June 30,
	2017			2016		2016

Derivative assets:
Derivatives not designated as cash flow hedging instruments:
Foreign exchange option contracts	$	221		$	-	$	214
Derivatives designated as cash flow hedging instruments:
Foreign exchange forward contracts		-			19		290

Total	$	221		$	19	$	504

Derivative liabilities:
Derivatives not designated as cash flow hedging instruments:
Foreign exchange option contracts	$	(285	)	$	-	$	(23	)
Foreign exchange forward contracts		(116	)		-		-

Total	$	(401	)	$	-	$	(23	)

The increase (decrease) in unrealized gains (losses) recognized in “accumulated other comprehensive income (loss)” on derivatives, net of tax effect, is as follows:

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Derivatives designated as cash flow hedging instruments:
Foreign exchange forward contracts	$	975	$	93	$	412	$	-

Total	$	975	$	93	$	412	$	-

The net (gains) losses reclassified from “accumulated other comprehensive income (loss)” into income (loss), are as follows:

	Year ended December 31,		Six months ended December 31,			Year ended June 30,
	2017		2016			2016			2015

Derivatives designated as cash flow hedging instruments:
Foreign exchange forward contracts	$	994	$	(317	)	$	(169	)	$	-

Total	$	994	$	(317	)	$	(169	)	$	-

The Company recorded in the financial income (expenses), a net gain (loss) of $1,334, $(87), $(136), and $1,721 during the year ended December 2017, the six months ended December 31, 2016, and years ended June 30, 2016 and 2015, respectively, related to derivatives not qualified as hedging instruments.

COMMITMENTS AND CONTINGENT LIABILITIES

12 Months Ended

Dec. 31, 2017

Commitments and Contingencies Disclosure [Abstract]

COMMITMENTS AND CONTINGENT LIABILITIES

NOTE 14:-

COMMITMENTS AND CONTINGENT LIABILITIES

Lease commitments:

The Company and its subsidiaries lease their operating facilities under non-cancelable operating lease agreements, which expire over the next ten years, with the last ending in September 2027.

On July 10, 2017 the Company entered into a ten years lease agreement, intended for the establishment of a manufacturing facility and includes three extension period options. The Company accounts for this lease as an operating lease according to ASC 840 (“Leases”).

The future minimum lease commitments of the Company and its subsidiaries under various non-cancelable operating lease agreements in respect of premises, that are in effect as of December 31, 2017, are as follows:

2018		4,520
2019		3,801
2020		3,094
2021		2,512
2022		2,472
2023 and thereafter		6,934

	$	23,333

Rent expenses for the year ended December 31, 2017, the six months ended December 31, 2016, and for the years ended June 30, 2016 and 2015 were approximately $3,449, $1,199, $2,238, and $1,714, respectively.

Guarantees:

As of December 31, 2017, contingent liabilities exist regarding guarantees in the amount of $1,191, $58, and $184 in respect of office rent lease agreements, customs transactions and credit card limits, respectively.

Governmental commitments:

The Company has received royalty-bearing grants sponsored by the Israeli government for the support of research and development activities. Through June 30, 2015, the Company had obtained grants from the IIA for certain of the Company’s research and development projects. The Company is obligated to pay royalties to the IIA, amounting to 4% in the first three years, and 4.5% thereafter, of the sales of the products and other related revenues (based on the dollar equivalent amount of the grant) generated from such projects, up to 100% of the grants received. The royalty payment obligations also bear interest at the LIBOR rate. The obligation to pay these royalties is contingent on actual sales of the applicable products and in the absence of such sales, no payment is required.

As of December 31, 2016, the aggregate contingent liability to the IIA with respect to royalty-bearing participation, net of royalties accrued, amounted to $1,022 out of which the Company already recorded a provision for royalties in the amount of $260. The total research and development grants that the Company has received from the IIA as of December 31, 2016 were $990. The accumulated interest as of December 31, 2016 was $32.

As of December 31, 2017, the Company redeemed its entire obligation to the IIA.

Royalty expenses relating to the IIA grants included in cost of revenues for the year ended December 31, 2017 and the six months ended December 31, 2016, amounted to $748 and $260, respectively.

As of June 30, 2016 and 2015, there have been no sales or revenues on which royalties are payables.

The Israeli Research and Development Law provides that know-how developed under an approved research and development program may not be transferred to third parties without the approval of the IIA. Such approval is not required for the sale or export of any products resulting from such research or development.

The IIA, under special circumstances, may approve the transfer of IIA-funded know-how outside Israel, in the following cases: (a) the grant recipient pays to the IIA a portion of the sale price paid in consideration for such IIA -funded know-how or in consideration for the sale of the grant recipient itself, as the case may be, which portion will not exceed six times the amount of the grants received plus interest (or three times the amount of the grant received plus interest, in the event that the recipient of the know-how has committed to retain the R&D activities of the grant recipient in Israel after the transfer); (b) the grant recipient receives know-how from a third party in exchange for its IIA-funded know-how; (c) such transfer of IIA-funded know-how arises in connection with certain types of cooperation in research and development activities; or (d) if such transfer of know-how arises in connection with a liquidation by reason of insolvency or receivership of the grant recipient.

Contractual purchase obligations:

The Company has contractual obligations to purchase goods and raw materials. These contractual purchase obligations relate to inventories held by contract manufacturers and purchase orders initiated by the contract manufacturers, which cannot be canceled without penalty. The Company utilizes third parties to manufacture its products.

In addition, it acquires raw materials or other goods and services, including product components, by issuing to suppliers authorizations to purchase based on its projected demand and manufacturing needs. As of December 31, 2017, the Company had non-cancelable purchase obligations totaling approximately $196,222, out of which the Company already recorded a provision for loss in the amount of $1,627 (see also Note 8).

As of December 31, 2017, the Company had contractual obligations for capital expenditures totaling approximately $23,263. These commitments reflect purchases of automated assembly lines and other machinery related to the Company’s manufacturing.

Legal claims:

From time to time, the Company may be involved in various claims and legal proceedings. The Company reviews the status of each matter and assesses its potential financial exposure. If the potential loss from any claim or legal proceeding is considered probable and the amount can be reasonably estimated, the Company accrues a liability for the estimated loss. These accruals are reviewed at least quarterly and adjusted to reflect the impact of negotiations, settlements, rulings, advice of legal counsel, and other information and events pertaining to a particular matter.

LEASE INCENTIVE OBLIGATION

12 Months Ended

Dec. 31, 2017

Leases [Abstract]

LEASE INCENTIVE OBLIGATION

NOTE 15:-

LEASE INCENTIVE OBLIGATION

The Company has an operating lease agreement for building in Herzliya, Israel. In connection with this lease, the Company and its third party lessor (the "Lessor") agreed that the Lessor would pay approximately $2,938 for certain leasehold improvements on behalf of the Company.

As of December 31, 2017, the Company received in cash the entire amount of $2,938 from the Lessor in connection with such leasehold improvements. These leasehold improvements are accounted for as a lease incentive obligation, which is recorded under long-term liabilities, net of the current portion recorded in accrued expenses and other accounts payable under current liabilities. The lease incentive obligation is being amortized over the life of the lease and as a reduction to rent expense. As of December 31, 2017, the net amortized amount of lease incentive obligation is $2,049, out of which $1,765 was recorded under long-term liabilities.

CONVERTIBLE PREFERRED STOCK

12 Months Ended

Dec. 31, 2017

Temporary Equity Disclosure [Abstract]

CONVERTIBLE PREFERRED STOCK

NOTE 16:-

CONVERTIBLE PREFERRED STOCK

Composition of convertible preferred stock of the Company:

	Authorized						Issued and outstanding
	Number of shares
	December 31,				June 30,		December 31,				June 30,
	2017		2016		2016		2017		2016		2016

Stock of $0.0001 par value:
Preferred stock		95,000,000		95,000,000		95,000,000		-		-		-

The Company issued Series A through E Preferred stock between the years 2006 and 2015. The Company classified the convertible preferred stock outside of stockholders’ equity (deficiency) as required by ASC 480-10-S99-3A and ASR 268, since the shares possessed deemed liquidation features that could trigger a distribution of cash or assets not solely within the Company’s control.

Prior to the consummation of the Company’s IPO on March 31, 2015, the Company had the following convertible preferred stock outstanding, all of which was converted into common stock following with the IPO on March 31, 2015 (see Note 1c) which resulted in classification of convertible preferred stock temporary equity in the amount of $140,915 into stockholders’ equity (deficiency):

	Shares outstanding		Number of shares of Common Stock issued upon conversion

Series A Preferred stock		15,558,830		5,186,276
Series B Preferred stock		18,760,196		6,253,398
Series C Preferred stock		15,984,655		5,328,217
Series D Preferred stock		16,024,251		5,341,416
Series D-1 Preferred stock		2,165,441		721,813
Series D-2 Preferred stock		2,598,528		866,175
Series D-3 Preferred stock		4,330,872		1,443,623
Series E Preferred stock		9,321,019		3,107,005
		84,743,792		28,247,923

STOCK CAPITAL

12 Months Ended

Dec. 31, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

STOCK CAPITAL

NOTE 17:-

STOCK CAPITAL

Composition of common stock capital of the Company:

	Authorized						Issued and outstanding
	Number of shares
	December 31,				June 30,		December 31,				June 30,
	2017		2016		2016		2017		2016		2016

Stock of $0.0001 par value:
Common stock		125,000,000		125,000,000		125,000,000		43,812,601		41,259,391		40,889,922

Common stock rights:

Common stock confers upon its holders the right to receive notice of, and to participate in, all general meetings of the Company, where each share of common stock shall have one vote for all purposes; to share equally, on a per share basis, in bonuses, profits, or distributions out of fund legally available therefor; and to participate in the distribution of the surplus assets of the Company in the event of liquidation of the Company.

As a result of the reverse stock split, (i) every 3 shares of authorized, issued, and outstanding common stock was decreased to one share of authorized, issued, and outstanding common stock, (ii) the number of shares of common stock into which each outstanding warrant or option to purchase common stock is exercisable was proportionally decreased on a 1-for-3 basis, and (iii) all share prices and exercise prices were proportionately increased. All of the share numbers, share prices, and exercise prices have been adjusted within these consolidated financial statements, on a retroactive basis, to reflect this 1-for-3 reverse stock split.

Stock option plans:

The Company’s 2007 Global Incentive Plan (the “2007 Plan”) was adopted by the board of directors on August 30, 2007. The 2007 Plan terminated upon the Company’s IPO on March 31, 2015 and no further awards may be granted thereunder. All outstanding awards will continue to be governed by their existing terms and 379,358 available options for future grant were transferred to the Company’s 2015 Global Incentive Plan (the “2015 Plan”) and are reserved for future issuances under the 2015 plan.

The 2015 Plan became effective upon the consummation of the IPO. The 2015 Plan provides for the grant of options, RSUs, and other share-based awards to directors, employees, officers, and consultants of the Company and its Subsidiaries. As of December 31, 2017, a total of 5,890,087 shares of common stock were reserved for issuance pursuant to stock awards under the 2015 Plan (the “Share Reserve”).

The Share Reserve will automatically increase on January 1st of each year during the term of the 2015 Plan, commencing on January 1st of the year following the year in which the 2015 Plan becomes effective, in an amount equal to 5% of the total number of shares of capital stock outstanding on December 31st of the preceding calendar year; provided, however, that the Company’s board of directors may determine that there will not be a January 1st increase in the Share Reserve in a given year or that the increase will be less than 5% of the shares of capital stock outstanding on the preceding December 31st.

The aggregate maximum number of shares of common stock that may be issued on the exercise of incentive stock options is 10,000,000. As of December 31, 2017, an aggregate of 2,003,126 options are still available for future grant under the 2015 Plan.

A summary of the activity in the share options granted to employees and members of the board of directors for the year ended December 31, 2017 and related information follows:

						Weighted
						average
				Weighted		remaining
	Number			average		contractual		Aggregate
	of			exercise		term		intrinsic
	options			price		in years		Value

Outstanding as of December 31, 2016		4,864,469			5.05		6.24		39,585
Granted		445,680			14.64
Exercised		(1,758,288	)		2.70
Forfeited or expired		(27,551	)		10.06
Outstanding as of December 31, 2017		3,524,310			7.40		6.35		106,251

Vested and expected to vest as of December 31, 2017		3,442,470			7.32		6.34		104,050

Exercisable as of December 31, 2017		2,406,369			5.58		5.64		76,931

The aggregate intrinsic value in the tables above represents the total intrinsic value (the difference between the fair value of the Company’s common stock as of the last day of each period and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised their options on the last day of each period.

The total intrinsic value of options exercised during the year ended December 31, 2017, the six months ended December 31, 2016, and the year ended June 30, 2016 was $44,625, $1,790, and $30,670, respectively.

The weighted average grant date fair values of options granted to employees and executive directors during the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015 were $7.94, $8.86, $13.27, and $4.24, respectively.

The options outstanding as of December 31, 2017, have been separated into exercise price ranges as follows:

		Options		Weighted		Options		Weighted
		outstanding		average		exercisable		average
Range of		as of		remaining		as of		remaining
exercise		December 31,		contractual		December 31,		contractual
price		2017		Life in years		2017		Life in years
$	0.87 - $1.50		202,281		1.44		202,281		1.44
$	1.68 - $2.46		660,264		3.68		660,264		3.68
$	3.03 - $5.01		1,778,547		6.81		1,263,352		6.79
$	9.36		15,267		7.08		8,949		7.08
$	13.70 – $14.85		438,430		9.12		78,309		9.02
$	15.34 – $17.14		193,571		8.61		60,314		8.49
$	20.81 - $25.09		235,950		7.57		132,900		7.49

			3,524,310		6.35		2,406,369		5.64

A summary of the activity in the RSUs granted to employees and members of the board of directors for the year ended December 31, 2017, is as follows:

	No. of RSUs			Weighted average grant date fair value
Unvested as of January 1, 2017		1,515,018			19.74
Granted		1,252,815			27.30
Vested		(547,104	)		20.07
Forfeited		(132,737	)		18.65
Unvested as of December 31, 2017		2,087,992			24.33

Options and RSUs issued to non-employee consultants:

The Company has granted options to purchase common shares and RSU’s to non-employee consultants as of December 31, 2017 as follows:

	Options & RSU’s
	outstanding				Exercisable
	as of				as of
Issuance	December 31,		Exercise		December 31,		Exercisable
Date	2017		price		2017		Through
October 24, 2012		2,000		2.46		2,000	October 24, 2022
January 27, 2014		1,144		3.51		713	January 27, 2024
May 1, 2014		2,000		3.51		1,875	May 1, 2024
September 17, 2014		6,498		3.96		5,509	September 17, 2024
October 29, 2014		2,668		5.01		224	October 29, 2024
August 19, 2015		10,439		0.00		-
November 8, 2015		1,449		0.00		-
April 18, 2016		1,250		0.00		-
July 11, 2016		1,501		0.00		-
September 21, 2016		4,000		15.34		250	September 21, 2026
September 21, 2016		3,813		0.00		-
March 15, 2017		7,000		0.00		-
March 15, 2017		7,500		13.70		500	March 15, 2027
March 27, 2017		4,000		0.00		-
November 20, 2017		6,000		0.00		-
December 26, 2017		2,667		0.00		667
		63,929				11,738

The Company accounts for its options granted to non-employee consultants under the fair value method of ASC 505-50 (“Equity-Based Payments to Non-Employees”).

In connection with the grant of stock options to non-employee consultants, the Company recorded stock compensation expenses in the year ended December 31, 2017, the six months ended December 31, 2016, and the years ended June 30, 2016 and 2015 in the amounts of $986, $66, $524, and $563, respectively.

Employee Stock Purchase Plan (“ESPP”):

The Company adopted an Employee Stock Purchase Plan (the “ESPP”) effective upon the consummation of the IPO. As of December 31, 2017, a total of 1,301,154 shares were reserved for issuance under this plan. The number of shares of common stock reserved for issuance under the ESPP will increase automatically on January 1st of each year, for ten years, by the lesser of 1% of the total number of shares of the Company’s common stock outstanding on December 31st of the preceding calendar year or 487,643 shares.

However, the Company’s board of directors may reduce the amount of the increase in any particular year at their discretion, including a reduction to zero.

The ESPP is implemented through an offering every six months. According to the ESPP, eligible employees may use up to 10% of their salaries to purchase common stock shares up to an aggregate limit of $10 per participant for every six months plan. The price of an ordinary share purchased under the ESPP is equal to 85% of the lower of the fair market value of the ordinary share on the subscription date of each offering period or on the purchase date.

As of December 31, 2017, 268,377 common stock shares had been purchased under the ESPP.

As of December 31, 2017, 1,032,777 common stock shares were available for future issuance under the ESPP.

In accordance with ASC No. 718, the ESPP is compensatory and, as such, results in recognition of compensation cost.

Stock-based compensation expense for employees and non-employee consultants:

The Company recognized stock-based compensation expenses related to stock options and RSUs granted to employees and non-employee consultants and ESPP in the consolidated statement of operations for the year ended December 31, 2017, the six months ended December 31, 2016, and for the years ended June 30, 2016 and 2015, as follows:

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Cost of revenues	$	2,250	$	871	$	945	$	442
Research and development, net		5,703		2,061		2,364		635
Selling and marketing		5,387		1,852		2,915		809
General and administrative		4,224		1,816		2,820		1,070

Total stock-based compensation expense	$	17,564	$	6,600	$	9,044	$	2,956

As of December 31, 2017, there was a total unrecognized compensation expense of $56,867 related to non-vested equity-based compensation arrangements granted under the Company’s Plans. These expenses are expected to be recognized during the period from January 1, 2018 through November 30, 2021.

INCOME TAXES

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

INCOME TAXES

NOTE 18:- INCOME TAXES

Tax rates in U.S:

The Company is subject to U.S. federal tax at the rate of 34%.

On December 22, 2017, the TCJA was signed into law making significant changes to U.S. income tax law. Changes include, but are not limited to, a corporate tax rate decrease from 35% to 21% effective for tax years beginning after December 31, 2017, the transition of U.S. international taxation from a worldwide tax system to a territorial system, and a one-time transition tax on the mandatory deemed repatriation of cumulative foreign earnings as of December 31, 2017. The Company has calculated its best estimate of the impact of the TCJA in its year end income tax provision in accordance with its understanding of the TCJA and guidance available as of the date of this filing and as a result has recorded $19.2 million as an additional income tax expense in the fourth quarter of 2017, the period in which the legislation was enacted.

The provisional amount related to the remeasurement of certain deferred tax assets and liabilities based on the rates at which they are expected to reverse in the future was $0.5 million. Additional work is necessary to reflect the actual rate at which those deferred tax assets and liabilities expected to reverse.

The provisional amount related to the one-time transition tax on the mandatory deemed repatriation of foreign earnings was $18.7 million based on cumulative foreign earnings of $145 million. Additional work is necessary to do a more detailed analysis of historical foreign earnings as well as potential correlative adjustments. Any subsequent adjustment to these amounts will be recorded to current tax expense in the quarter of 2018 when the analysis is complete.

Additionally, the Tax Act requires certain Global Intangible Low Taxed Income (“GILTI”) earned by controlled foreign corporations (“CFCs”) to be included in the gross income of the CFCs’ U.S. shareholder. GAAP allows the Company to either: (i) treat taxes due on future U.S. inclusions in taxable income related to GILTI as a current-period expense when incurred (the “period cost method”); or (ii) factor such amounts into its measurement of deferred taxes (the “deferred method”). The GILTI tax rules will become effective for the 2018 tax year and therefore the Company has not made any adjustments related to the potential GILTI tax in its financial statements for the year ended December 31, 2017. The Company continues to evaluate the impact of the new GILTI tax rules and the application of ASC 740 on its financial statements.

The Company’s German subsidiary is subject to German tax at the rate of 33%.

Corporate tax in Israel:

Taxable income of Israeli companies is subject to corporate tax at the rate of 26.5% in the years ended June 30, 2014 and 2015, and 25% in the year ended June 30, 2016 onwards.

The Israeli subsidiary is also eligible for tax benefits as further described in note 18k.

In December 2016, the Israeli Parliament approved the Economic Efficiency Law 2016 (Legislative Amendments for Applying the Economic Policy for the 2017 and 2018 Budget Years), which reduces the corporate income tax rate to 24% (instead of 25%) effective from January 1, 2017 and to 23% effective from January 1, 2018.

Carryforward tax losses:

As of December 31, 2017, the Company has no federal or state carryforward tax losses.

As of December 31, 2017, the Israeli and German subsidiaries have no net carryforward tax losses.

Deferred income taxes:

Deferred income taxes reflect the net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes.

The Company’s Israeli subsidiary’s tax-exempt profit from Benefited Enterprises is permanently reinvested, as the Company’s management and the Board of Directors has determined that the Company does not currently intend to distribute dividends. Therefore, deferred taxes have not been provided for such tax-exempt income. The Company intends to continue to reinvest these profits and does not currently foresee a need to distribute dividends out of such tax-exempt income.

Significant components of the Company’s deferred tax liabilities and assets are as follows:

	December 31,				June 30,
	2017		2016		2016

Assets in respect of:

Carryforward tax losses	$	-	$	-	$	4,186
Research and Development carryforward expenses- temporary differences		5,380		908		743
Stock based compensation		1,622		1,039		562
Other reserves		1,338		868		805

Deferred tax assets, net	$	8,340	$	2,815	$	6,296

The Company remeasured these non-current assets and liabilities at the applicable tax rate of 21% in accordance with the TCJA. The remeasurement resulted in a total decrease in these assets of $0.5 million.

Uncertain tax positions:

As of December 31, 2017 and 2016, the Company’s Israeli subsidiary recognized a total liability for uncertain tax positions in the amount of $0.6 and $0.3 million, respectively.

Income before taxes is comprised as follows:

	Year Ended December 31, 2017		Six months ended December 31, 2016		Year ended June 30,
	Year Ended December 31, 2017		Six months ended December 31, 2016		2016		2015

Domestic	$	7,461	$	3,165	$	3,758	$	2,830
Foreign		92,783		27,433		68,472		20,246

	$	100,244	$	30,598	$	72,230	$	23,076

Taxes on income (tax benefit) are comprised as follows:

	Year ended December 31, 2017			Six months ended December 31, 2016		Year ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016		2016			2015
Domestic taxes:
Current		19,889			1,047		1,737			1,655
Deferred		(42	)		507		(1,380	)		-
Foreign taxes:
Current		1,639			518		263			300
Deferred		(5,414	)		3,145		(4,999	)		-

	$	16,072		$	5,217	$	(4,379	)	$	1,955

Reconciliation of theoretical tax expense to actual tax expense:

The differences between the statutory tax rate of the Company and the effective tax rate are primarily accounted for by the non-recognition of tax benefits from accumulated net carryforward tax losses among the Company and various subsidiaries due to uncertainty of the realization of such tax benefits.

A reconciliation between the theoretical tax expense, assuming all income is taxed at the statutory tax rate applicable to income of the Company, and the actual tax expense (benefit) as reported in the consolidated statements of operations is as follows:

	Year ended December 31,			Six months ended December 31,			Year ended June 30,
	2017			2016			2016			2015

Income before taxes, as reported in the consolidated statements of operations	$	100,244		$	30,598		$	72,230		$	23,076

Statutory tax rate		34	%		34	%		34	%		35	%
Theoretical tax benefits on the above amount at the US statutory tax rate		34,083			10,403			24,558			8,077
Income tax at rate other than the U.S. statutory tax rate		(34,734	)		(5,396	)		(30,229	)		(9,305	)
Tax Cuts and Jobs Act of 2017		18,735			-			-			-
Non-deductible expenses		(1,545	)		164			1,514			3,003
Other individually immaterial income tax items		(467	)		46			(222	)		180

Actual tax expense (tax benefit)	$	16,072		$	5,217		$	(4,379	)	$	1,955

Tax assessments:

As of December 31, 2017, the Company and certain of its subsidiaries filed U.S. federal and various state and foreign income tax returns. The statute of limitations relating to the consolidated U.S. federal income tax return is closed for all tax years up to and including 2014.

The statute of limitations related to tax returns of the Company’s Israeli subsidiary is closed for all tax years up to and including 2012.

The statute of limitations related to tax returns of the Company’s German subsidiary is closed for all tax years up to and including 2014.

With respect to the Company’s Chinese, Australian, Canadian, Dutch, Japanese, UK, French, Italian, Bulgarian, Turkish, Belgian, Indian, Swedish, and Romanian subsidiaries, the statute of limitations related to its tax returns is open for all tax years since incorporation.

The Company believes that it has adequately provided for reasonably foreseeable outcomes related to tax audits and settlements. The final tax outcome of any Company tax audits could be different from that which is reflected in the Company’s income tax provisions and accruals. Such differences could have a material effect on the Company’s income tax provision and net income (loss) in the period in which such determination is made.

Tax benefits for Israeli companies under the Law for the Encouragement of Capital Investments, 1959 (the “Investment Law”):

The Israeli subsidiary elected tax year 2012 as a "Year of Election" for “Beneficiary Enterprise” status under the Investment Law. According to the Investment Law, the Israeli subsidiary elected to participate in the alternative benefits program which provides certain benefits, including tax exemptions and reduced tax rates. Income not eligible for Beneficiary Enterprise benefits is taxed at a regular corporate tax rate (which depend on, inter alia, the geographic location in Israel). Upon meeting the requirements under the Investment Law, undistributed income derived from Beneficiary Enterprise from productive activity will be exempt from tax for two years from the year in which the Israeli subsidiary first has taxable income, provided that 12 years have not passed from the beginning of the year of election. In the six months ended December 31, 2016, the Israeli subsidiary utilized all of its operating loss carryforwards in Israel and became profitable for tax purposes. As of December 31, 2017, the Israeli subsidiary is entitled to benefit from a two year tax exemption as part of the Beneficiary Enterprise regime.

If dividends are distributed out of tax-exempt profits, the Israeli subsidiary will then become liable for tax, with respect of the gross amount of the dividend at the rate applicable to its profits from the Beneficiary Enterprise in the year in which the income was earned, as if it had not chosen the alternative track of benefits.

The dividend recipient is subject to withholding tax at the rate of 15% applicable to dividends from Beneficiary enterprises, or such lower rate as may be provided in an applicable tax treaty. If the dividend is distributed during the tax benefits period or within twelve years thereafter. This limitation does not apply to a foreign investors' company. The Israeli subsidiary currently has no plans to distribute dividends and intends to retain future earnings to finance the development of its business.

Through December 31, 2017, the Israeli subsidiary had generated income under the provision of the Investment Law.

As of December 31, 2017, approximately $151 million was derived from tax exempt profits earned by the Israeli subsidiary “Beneficiary Enterprises.” The Company has determined that such tax-exempt income will not be distributed as dividends and intends to reinvest the amount of its tax exempt income earned by the Israeli subsidiary. Accordingly, no provision for deferred income taxes has been provided on income attributable to the Israeli subsidiary “Beneficiary Enterprises” as such income is essentially permanently reinvested.

If the Israeli subsidiary retained tax-exempt income is distributed, the income would be taxed at the applicable corporate tax rate which depend on the foreign ownership in each tax year, the tax rate can range between 10% (when foreign ownership exceeds 90%) to 25% (when foreign ownership exceeds 49%).

Amendment to the Law for the Encouragement of Capital Investments, 1959 (Amendment 71):

On August 5, 2013, the Israeli Parliament issued the Law for Changing National Priorities (Legislative Amendments for Achieving Budget Targets for 2013 and 2014), 2013 which consists of Amendment 71 to the Law for the Encouragement of Capital Investments ("the Amendment"). According to the Amendment, the tax rate on preferred income from a preferred enterprise in 2014 and thereafter will be 16% (in development area A (as defined therein and which details specific areas in development in Israel) will be 9%).

The Amendment also prescribes that any dividends distributed to individuals or foreign residents from the preferred enterprise's earnings as above will be subject to tax at a rate of 20%.

Amendment to the Law for the Encouragement of Capital Investments, 1959 (Amendment 73):

In December 2016, the Economic Efficiency Law (Legislative Amendments for Applying the Economic Policy for the 2017 and 2018 Budget Years), 2016 which includes Amendment 73 to the Law for the Encouragement of Capital Investments ("the 2017 Amendment") was published. According to the 2017 Amendment, a preferred enterprise located in development area A will be subject to a tax rate of 7.5% instead of 9% effective from January 1, 2017 and thereafter (the tax rate applicable to preferred enterprises located in other areas remains at 16%).

The 2017 Amendment also prescribes special tax tracks for technological enterprises, which are subject to rules that were issued by the Ministry of Finance.

The new tax tracks under the 2017 Amendment are as follows:

According to the 2017 Amendment, preferred technological enterprise is an enterprise for which total consolidated revenues of its parent company and all subsidiaries are less than NIS 10 billion. A technological preferred enterprise, as defined in the Investment Law, which is located in the center of Israel will be subject to tax at a rate of 12% on profits deriving from intellectual property (in development area A - a tax rate of 7.5%).

Special preferred technological enterprise is an enterprise for which total consolidated revenues of its parent company and all subsidiaries exceed NIS 10 billion. Such enterprise will be subject to tax at a rate of 6% on profits deriving from intellectual property, regardless of the enterprise's geographical location.

Any dividends distributed deriving from income from the preferred technological enterprises or special preferred technological enterprise will be subject to tax at a rate of 20%. The 2017 Amendment further provides that, in certain circumstances, a dividend distributed to a foreign corporate shareholder, would be subject to tax at a rate of 4% (if the amount of foreign investors exceeds 90%).

The Israeli subsidiary is entitle to the above mentioned preferred technological enterprise benefits and will be subject to tax at a rate of 12% on profits deriving from intellectual property or 7.5% in development area A, under the 2017 Amendment.

Tax Benefits for Research and Development:

Israeli tax law (section 20a to the Israeli Tax Ordinance) allows, under certain conditions, a tax deduction for research and development expenses, including capital expenses, for the year in which they are paid. Such expenses must relate to scientific research in industry, agriculture, transportation, or energy, and must be approved by the relevant Israeli government ministry, determined by the field of research. Furthermore, the research and development must be for the promotion of the company’s business and carried out by or on behalf of the company seeking such tax deduction. However, the amount of such deductible expenses is reduced by the sum of any funds received through government grants for the finance of such scientific research and development projects. As for expenses incurred in scientific research that is not approved by the relevant Israeli government ministry, they will be deductible over a three-year period starting from the tax year in which they are paid.

FINANCIAL EXPENSES (INCOME), NET

12 Months Ended

Dec. 31, 2017

Nonoperating Income (Expense) [Abstract]

FINANCIAL EXPENSES (INCOME), NET

NOTE 19:-

FINANCIAL EXPENSES (INCOME), NET

	Year ended December 31,			Six months ended December 31,			Year ended June 30,
	2017			2016			2016			2015

Remeasurement of warrants to purchase convertible preferred stock	$	-		$	-		$	-		$	5,350
Interest on term loan		-			-			-			579
Other financial expenses related to term loan		-			-			-			373
Expenses (income) related to hedging transaction		1,334			87			136			(1,721	)
Interest on short- term loan		-			-			-			316
Interest on marketable securities		(4,398	)		(1,504	)		(1,112	)		-
Amortization of marketable securities premium and accretion of discount, net		2,017			685			532			-
Exchange rate loss (income), net, bank charges and other finance expenses		(8,111	)		3,521			(27	)		180

	$	(9,158	)	$	2,789		$	(471	)	$	5,077

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA

12 Months Ended

Dec. 31, 2017

Segment Reporting [Abstract]

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA

NOTE 20:-

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA

Summary information about geographic areas:

ASC 280 (“Segment Reporting”) establishes standards for reporting information about operating segments. Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing performance. The Company manages its business on the basis of one reportable segment, and derives revenues from selling its products (see Note 1a for a brief description of the Company’s business).

The following is a summary of revenues within geographic areas:

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Revenues based on Customers’ location:
United States	$	348,949	$	160,321	$	334,260	$	238,340
Netherlands		70,067		23,099		36,377		21,349
Europe (*)		128,295		37,500		74,830		44,104
Rest of the World		59,734		19,077		44,376		21,285
Total revenues	$	607,045	$	239,997	$	489,843	$	325,078

(*) Except for Netherlands

Major customer data as a percentage of total revenues:

	Year ended December 31,			Six months ended December 31,			Year ended June 30,
	2017			2016			2016			2015

Customer A		14.8	%		11.2	%		11.6	%		4.9	%
Customer B		8.1	%		8.4	%		10.1	%		5.4	%
Customer C		3.0	%		8.7	%		10.9	%		24.6	%

The following is a summary of revenues by product family :

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Inverters	$	290,632	$	112,585	$	223,756	$	156,984
Optimizers		286,856		115,229		244,852		158,513
Others		29,557		12,183		21,235		9,581
Total revenues	$	607,045	$	239,997	$	489,843	$	325,078

Long-lived assets by geographic region:

	As of December 31,				As of June 30,
	2017		2016		2016

Israel	$	43,273	$	35,055	$	26,751
U.S.		567		515		518
Europe		1,219		466		508
China		5,985		36		31
Other		138		50		23

Total long-lived assets*	$	51,182	$	36,122	$	27,831

Long-lived assets are comprised of property and equipment, net (marketable securities, prepaid expenses, and lease deposits, intangible assets and deferred tax assets are not included).

SIGNIFICANT ACCOUNTING POLICIES (Policies)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Principles of consolidation

Principles of consolidation:

Use of estimates

Use of estimates:

Financial statements in U.S. dollars

Financial statements in U.S. dollars:

The resulting translation adjustments are reported as a component of stockholders’ equity in accumulated other comprehensive income.

Accumulated other comprehensive loss related to foreign currency translation adjustments, net amounted to $178, $207, and $29 as of December 31, 2017 and 2016, and June 30, 2016, respectively.

Basic and Diluted Net Earnings Per Share

Basic and Diluted Net Earnings Per Share:

Basic net earnings per share is computed by dividing the net earnings by the weighted-average number of shares of common stock outstanding during the period.

The following table presents the computation of basic and diluted net earnings per share for the periods presented (in thousands, except share and per share data):

	Year ended		Six months Ended		Year ended June 30,
	December 31, 2017		December 31, 2016		2016		2015
Net basic earnings (loss) per share of common stock:
Numerator:
Net income	$	84,172	$	25,381	$	76,609	$	21,121
Dividends accumulated for the period		-		-		-		(17,550	)
Net income available to shareholders of common stock		84,172		25,381		76,609		3,571

Denominator:
Shares used in computing net earnings per share of common stock, basic		42,209,238		41,026,926		39,987,935		11,902,911

Net diluted earnings per share of common stock:
Numerator:
Net income		84,172		25,381		76,609		21,121
Dividends accumulated for the period		-		-		-		(16,971	)
Net income available to shareholders of common stock		84,172		25,381		76,609		4,150

Denominator:
Shares used in computing net earnings per share of common stock, basic		42,209,238		41,026,926		39,987,935		11,902,911
Effect of stock-based awards		3,216,069		2,812,416		4,388,140		3,366,537
Shares used in computing net earnings per share of common stock, diluted		45,425,307		43,839,342		44,376,075		15,269,448

Basic net income per share	$	1.99	$	0.62	$	1.92	$	0.30
Diluted net income per share	$	1.85	$	0.58	$	1.73	$	0.27

Cash and cash equivalents

Cash and cash equivalents:

Cash equivalents are short-term, highly liquid investments that are readily convertible to cash, with original maturities of three months or less at the date acquired.

Marketable Securities

Marketable Securities:

Restricted cash

Restricted cash:

Inventories

Inventories:

Inventories are stated at the lower of cost or market value. Inventory reserves are provided to cover risks arising from slow-moving items or technological obsolescence.

Property, equipment and intangible assets

Property, equipment, and intangible assets:

Property and equipment:

		%

Computers and peripheral equipment		15 – 33 (mainly 33)
Office furniture and equipment		7
Machinery & equipment		7 – 20 (mainly 10)
Laboratory equipment		15 – 25 (mainly 15)
Vehicles		15
Leasehold improvements		over the shorter of the lease term or useful economic life

Intangible assets:

Intangible assets are stated at cost, net of accumulated amortization. Amortization is calculated by the straight-line method over the estimated useful lives of the assets (see Note 7).

Impairment of long-lived assets

Impairment of long-lived assets:

Severance pay

k. Severance pay:

Revenue recognition

Revenue recognition:

Provisions for rebates, sales incentives, and discounts to customers are accounted for as reductions in revenue in the same period the related sales are recorded.

Revenues related to cloud-based monitoring and communication services are recognized ratably on a straight-line basis over the estimated service period.

The Company’s process for determining its ESP considers multiple factors that may vary depending upon the unique facts and circumstances related to each deliverable.

Cost of revenues

Cost of revenues:

Shipping and handling costs

Shipping and handling costs:

Warranty obligations

Warranty obligations:

The Company performs accelerated life cycle testing, which simulates the service life of the product in a short period of time.

Warranty obligations are classified as short-term and long-term obligations based on the period in which the warranty is expected to be claimed.

Government grants

Government grants:

The Company recorded grants in the amount of $763 for the year ended June 30, 2015, which was deducted from research and development expenses.

No grants were recorded for the year ended December 31, 2017, the six months ended December 31, 2016, and for the year ended June 30, 2016.

Research and development costs

Research and development costs:

Research and development costs, net of grants received, are charged to the consolidated statement of operations as incurred.

Concentrations of credit risks

Concentrations of credit risks:

The Company’s marketable securities consist of corporate and governmental bonds.

The trade receivables of the Company are derived from sales to Customers located primarily in North America, Europe, and Australia.

The Company generally does not require collateral, however, in certain circumstances, the Company may require letters of credit, other collateral, or additional guarantees.

In addition, an accrual for rebates is allocated to specific debts. The Company accrued $17,428, $9,089, and $4,294 for rebates as of December 31, 2017 and 2016 and June 30, 2016, respectively.

The Company and its subsidiaries have no off-balance sheet concentration of credit risk except for certain derivative instruments as mentioned below.

Fair value of financial instruments

s. Fair value of financial instruments:

The following methods and assumptions were used by the Company in estimating the fair value of its financial instruments:

The Company applies ASC 820 (“Fair Value Measurements and Disclosures”), with respect to fair value measurements of all financial assets and liabilities.

A three-tiered fair value hierarchy is established as a basis for considering such assumptions and for inputs used in the valuation methodologies in measuring fair value:

Level 1-

Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets.

Level 2-

Include other inputs that are directly or indirectly observable in the marketplace.

Level 3-

Unobservable inputs which are supported by little or no market activity.

The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value.

Warrants to Purchase Convertible Preferred Stock

Warrants to Purchase Convertible Preferred Stock:

The dividend yield assumption was zero, as there is no history of dividend payments and the Company does not expect to pay any dividends in the foreseeable future.

The following assumptions were used to estimate the value of the warrants to purchase convertible preferred stock:

	June 30,
	2014

Expected volatility		45.0	%
Risk-free rate		0.09	%
Dividend yield		0	%
Expected term (in years)		1.21

The change in the fair value of warrants to purchase convertible preferred stock is summarized below:

	Balance at beginning of period		Issuance of warrants to purchase preferred stock		Exercise of warrants to purchase common stock (*)			Change in fair value		Balance at end of period

June 30, 2015	$	765	$	-	$	(6,115	)	$	5,350	$	-

(*)

Upon the closing of the IPO, all outstanding warrants to purchase convertible preferred stock automatically converted into warrants to purchase 187,671 shares of common stock (See Note 1c).

Accounting for stock-based compensation

Accounting for stock-based compensation:

	Year ended December 31, 2017			Six months ended December 31, 2016			Year Ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016			2016			2015
Employee Stock Options
Risk-free interest		2.14% - 2.17	%		1.28% - 1.34	%		1.39% - 1.97	%		1.39% - 2.06	%
Dividend yields		0	%		0	%		0	%		0	%
Volatility		58.08% - 58.10	%		55.33% - 55.34	%		55.45%-56.03	%		46.5%-55.1	%
Expected option term in years		6.06			6.06			5.50-6.11			5.50-6.27
Estimated forfeiture rate		0	%		0	%		10.3	%		12.5%-18.7	%
Employee Stock Purchase Plan
Risk-free interest		0.6% - 1.07	%		0.60	%		0.40	%		-
Dividend yields		0	%		0	%		0	%		-
Volatility		45.6% - 48.08	%		48.08	%		62.84	%		-
Expected term	6 months			6 months			6 months				-

	Year ended December 31, 2017			Six months ended December 31, 2016			Year ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016			2016			2015

Risk-free interest		2.12% - 2.42	%		1.16% - 2.45	%		1.15%-2.21	%		1.59%-2.58	%
Dividend yields		0	%		0	%		0	%		0	%
Volatility		61.21% - 62.62	%		55.33% - 58.57	%		55.37%-55.75	%		45.5%-56.2	%
Contractual life in years		6-10			6 - 10			6.4-10			7.4-10

Income taxes

Income taxes:

The Company record reserves for uncertain tax positions to the extent it is more likely than not that the tax position will be sustained on audit, based on the technical merits of the position.

Derivative financial instruments

Derivative financial instruments:

As of December 31, 2017, the Company entered into forward contracts and put and call options to sell Euros for U.S. dollars in the amount of €54 million.

As of December 31, 2017, the Company had no derivative instruments that are designated as cash flow hedges.

As of December 31, 2016, the Company had no derivative instruments that are not designated as cash flow hedges.

The fair value of derivative assets as of December 31, 2016 was $19, which was recorded in other accounts receivable and prepaid expenses in the consolidated balance sheets (see Note 13).

The Company recorded changes in the fair value (i.e., gains or losses) of the derivatives in the accompanying consolidated statements of cash flows as changes in operating activities.

Comprehensive income

Comprehensive income:

New accounting pronouncements not yet effective:

Recently issued and adopted pronouncements

<div><div style="text-align: justify; line-height: 1.25"><table id="z18dce953167c4d83820117a005e36110" class="DSPFListTable" cellspacing="0" cellpadding="0" style="font: 10pt Times New Roman, Times, serif; width: 100%"><tr><td style="width: 56.7pt"></td> <td style="font: 10pt Times New Roman, Times, serif; vertical-align: top; width: 28.35pt">aa.</td> <td style="vertical-align: top; text-align: justify; width: auto"> <div style="font: 10pt Times New Roman, Times, serif">Recently issued and adopted pronouncements:</div> </td> </tr> </table> </div> <div style="line-height: 1.25"><br style="line-height: 1.25" /> </div> <div style="font: 10pt/1.25 Times New Roman, Times, serif; text-align: justify; margin-left: 85.05pt; background-color: #ffffff">In July 2015, the FASB issued ASU No. 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory (“ASU 2015-11”). The new standard applies only to inventory for which cost is determined by methods other than last-in, first-out or the retail inventory method, such as inventory measured using first-in, first-out, or average cost. Inventory within the scope of ASU 2015-11 is required to be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The Company adopted ASU 2015-11 during the first quarter of 2017, which did not have a material impact on our results of operations, cash flows, or financial position.</div></div>

SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2017

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions used to estimate fair value of stock options and warrants

The following assumptions were used to estimate the value of the warrants to purchase convertible preferred stock:

	June 30,
	2014

Expected volatility		45.0	%
Risk-free rate		0.09	%
Dividend yield		0	%
Expected term (in years)		1.21

Schedule of computation of basic and diluted net earnings (loss) per share

The following table presents the computation of basic and diluted net earnings per share for the periods presented (in thousands, except share and per share data):

	Year ended		Six months Ended		Year ended June 30,
	December 31, 2017		December 31, 2016		2016		2015
Net basic earnings (loss) per share of common stock:
Numerator:
Net income	$	84,172	$	25,381	$	76,609	$	21,121
Dividends accumulated for the period		-		-		-		(17,550	)
Net income available to shareholders of common stock		84,172		25,381		76,609		3,571

Denominator:
Shares used in computing net earnings per share of common stock, basic		42,209,238		41,026,926		39,987,935		11,902,911

Net diluted earnings per share of common stock:
Numerator:
Net income		84,172		25,381		76,609		21,121
Dividends accumulated for the period		-		-		-		(16,971	)
Net income available to shareholders of common stock		84,172		25,381		76,609		4,150

Denominator:
Shares used in computing net earnings per share of common stock, basic		42,209,238		41,026,926		39,987,935		11,902,911
Effect of stock-based awards		3,216,069		2,812,416		4,388,140		3,366,537
Shares used in computing net earnings per share of common stock, diluted		45,425,307		43,839,342		44,376,075		15,269,448

Basic net income per share	$	1.99	$	0.62	$	1.92	$	0.30
Diluted net income per share	$	1.85	$	0.58	$	1.73	$	0.27

Schedule of estimated useful lives of property and equipment

Depreciation is calculated by the straight-line method over the estimated useful lives of the assets, at the following rates:

		%

Computers and peripheral equipment		15 – 33 (mainly 33)
Office furniture and equipment		7
Machinery & equipment		7 – 20 (mainly 10)
Laboratory equipment		15 – 25 (mainly 15)
Vehicles		15
Leasehold improvements		over the shorter of the lease term or useful economic life

Summary of change in fair value of warrants to purchase convertible preferred stock

The change in the fair value of warrants to purchase convertible preferred stock is summarized below:

	Balance at beginning of period		Issuance of warrants to purchase preferred stock		Exercise of warrants to purchase common stock (*)			Change in fair value		Balance at end of period

June 30, 2015	$	765	$	-	$	(6,115	)	$	5,350	$	-

(*)

Upon the closing of the IPO, all outstanding warrants to purchase convertible preferred stock automatically converted into warrants to purchase 187,671 shares of common stock (See Note 1c).

Employee Stock Option [Member] | Employees and Members of Board of Directors [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions used to estimate fair value of stock options and warrants

	Year ended December 31, 2017			Six months ended December 31, 2016			Year Ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016			2016			2015
Employee Stock Options
Risk-free interest		2.14% - 2.17	%		1.28% - 1.34	%		1.39% - 1.97	%		1.39% - 2.06	%
Dividend yields		0	%		0	%		0	%		0	%
Volatility		58.08% - 58.10	%		55.33% - 55.34	%		55.45%-56.03	%		46.5%-55.1	%
Expected option term in years		6.06			6.06			5.50-6.11			5.50-6.27
Estimated forfeiture rate		0	%		0	%		10.3	%		12.5%-18.7	%
Employee Stock Purchase Plan
Risk-free interest		0.6% - 1.07	%		0.60	%		0.40	%		-
Dividend yields		0	%		0	%		0	%		-
Volatility		45.6% - 48.08	%		48.08	%		62.84	%		-
Expected term	6 months			6 months			6 months				-

Employee Stock Option [Member] | Nonemployee Consultants [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of assumptions used to estimate fair value of stock options and warrants

	Year ended December 31, 2017			Six months ended December 31, 2016			Year ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016			2016			2015

Risk-free interest		2.12% - 2.42	%		1.16% - 2.45	%		1.15%-2.21	%		1.59%-2.58	%
Dividend yields		0	%		0	%		0	%		0	%
Volatility		61.21% - 62.62	%		55.33% - 58.57	%		55.37%-55.75	%		45.5%-56.2	%
Contractual life in years		6-10			6 - 10			6.4-10			7.4-10

Tabular disclosure of warrants or rights issued. Warrants and rights outstanding are derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential. The main difference between warrants and call options is that warrants are issued and guaranteed by the company, whereas options are exchange instruments and are not issued by the company. Also, the lifetime of a warrant is often measured in years, while the lifetime of a typical option is measured in months. Disclose the title of issue of securities called for by warrants and rights outstanding, the aggregate amount of securities called for by warrants and rights outstanding, the date from which the warrants or rights are exercisable, and the price at which the warrant or right is exercisable.

Schedule of Available-For-Sale Marketable Securities

MARKETABLE SECURITIES (Tables)

12 Months Ended

Dec. 31, 2017

Marketable Securities Tables

The following is a summary of available-for-sale marketable securities at December 31, 2017:

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value

Available for-sale – matures within one year:
Corporate bonds	$	68,392	$	1	$	(121	)	$	68,272
Governmental bonds		9,019		-		(27	)		8,992
		77,411		1		(148	)		77,264

Available for-sale – matures after one year:
Corporate bonds		95,540		-		(380	)		95,160
Governmental bonds		8,023		-		(63	)		7,960
		103,563		-		(443	)		103,120

Total	$	180,974	$	1	$	(591	)	$	180,384

The following is a summary of available-for-sale marketable securities at December 31, 2016:

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value

Available for-sale – matures within one year:
Corporate bonds	$	71,753	$	20	$	(54	)	$	71,719
Governmental bonds		2,758		-		(12	)		2,746
		74,511		20		(66	)		74,465

Available for-sale – matures after one year:
Corporate bonds		39,435		3		(159	)		39,279
Governmental bonds		5,004		-		(21	)		4,983
		44,439		3		(180	)		44,262

Total	$	118,950	$	23	$	(246	)	$	118,727

The following is a summary of available-for-sale marketable securities at June 30, 2016:

	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value

Available for-sale – matures within one year:
Corporate bonds	$	57,119	$	50	$	(11	)	$	57,158
Governmental bonds		2,005		-		-			2,005
		59,124		50		(11	)		59,163

Available for-sale – matures after one year:
Corporate bonds		46,375		86		(31	)		46,430
Governmental bonds		6,015		7		(6	)		6,016
		52,390		93		(37	)		52,446

Total	$	111,514	$	143	$	(48	)	$	111,609

Schedule of Amortized Cost of Available-For-Sale Marketable Securities

	Less than 12 months					12 months or greater
	Fair value		Gross unrealized losses			Fair value		Gross unrealized losses

As of December 31, 2017	$	72,269	$	(148	)	$	103,116	$	(443	)
As of December 31, 2016	$	51,124	$	(66	)	$	39,373	$	(180	)
As of June 30, 2016	$	22,895	$	(11	)	$	20,070	$	(37	)

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

Schedule of Assets and Liabilities Measured at Fair Value

FAIR VALUE MEASUREMENTS (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Measurements Tables

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2017 by level within the fair value hierarchy:

	Balance as of			Fair value measurements
Description	December 31, 2017			Level 1		Level 2			Level 3

Cash equivalents:
Money market mutual funds	$	6,163		$	6,163		-			-

Derivative instruments liability	$	(180	)		-	$	(180	)		-

Short-term marketable securities:
Corporate bonds	$	68,272			-	$	68,272			-
Governmental bonds	$	8,992			-	$	8,992			-

Long-term marketable securities:
Corporate bonds	$	95,160			-	$	95,160			-
Governmental bonds	$	7,960			-	$	7,960			-

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2016 by level within the fair value hierarchy:

	Balance as of		Fair value measurements
Description	December 31, 2016		Level 1		Level 2		Level 3

Cash equivalents:
Money market mutual funds	$	6,510	$	6,510		-		-

Derivative instruments asset	$	19		-	$	19		-

Short-term marketable securities:
Corporate bonds	$	71,719		-	$	71,719		-
Governmental bonds	$	2,746		-	$	2,746		-

Long-term marketable securities:
Corporate bonds	$	39,279		-	$	39,279		-
Governmental bonds	$	4,983		-	$	4,983		-

The following table sets forth the Company’s assets that were measured at fair value as of June 30, 2016 by level within the fair value hierarchy:

	Balance as of		Fair value measurements
Description	June 30, 2016		Level 1		Level 2		Level 3

Cash equivalents:
Money market mutual funds	$	13,373	$	13,373		-		-

Derivative instruments asset	$	481		-	$	481		-

Short-term marketable securities:
Corporate bonds	$	57,158		-	$	57,158		-
Governmental bonds	$	2,005		-	$	2,005		-

Long-term marketable securities:
Corporate bonds	$	46,430		-	$	46,430		-
Governmental bonds	$	6,016		-	$	6,016		-

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

PREPAID EXPENSES AND OTHER ACCOUNTS RECEIVABLE (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of prepaid expenses and other accounts receivable

	December 31,				June 30,
	2017		2016		2016

Vendor non-trade receivables (*)	$	33,719	$	15,209	$	15,375
Government authorities		3,421		2,585		2,727
Prepaid expenses and other		5,083		3,534		2,756
Foreign currency derivative contracts		-		19		482

	$	42,223	$	21,347	$	21,340

INVENTORIES (Tables)

12 Months Ended

Dec. 31, 2017

Inventory Disclosure [Abstract]

Schedule of inventories

	December 31,				June 30,
	2017		2016		2016

Raw materials	$	25,887	$	10,053	$	9,805
Finished goods		57,105		57,310		71,745

	$	82,992	$	67,363	$	81,550

PROPERTY AND EQUIPMENT AND INTANGIBLE ASSETS, NET (Tables)

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Schedule of property and equipment

Property and equipment:

	As of December 31,				As of June 30,
	2017		2016		2016

Cost:

Computers and peripheral equipment	$	9,872	$	6,053	$	5,190
Office furniture and equipment		1,785		1,505		1,289
Laboratory and testing equipment		13,732		9,589		8,590
Machinery and equipment		38,422		26,285		18,433
Leasehold improvements		7,536		5,898		5,450
Vehicles		39		13		13

		71,386		49,343		38,965

Less - accumulated depreciation		20,204		13,221		11,134

Depreciated cost	$	51,182	$	36,122	$	27,831

ACCRUED EXPENSES AND OTHER ACCOUNTS PAYABLE (Tables)

12 Months Ended

Dec. 31, 2017

Payables and Accruals [Abstract]

Schedule of accrued expenses and other accounts payable

	As of December 31,				As of June 30,
	2017		2016		2016

Accrued expenses	$	14,863	$	4,209	$	5,615
Government authorities		1,905		1,568		1,406
Loss provision related to contractual inventory purchase obligations *		1,627		2,009		2,834
Other		1,983		862		870

	$	20,378	$	8,648	$	10,725

See also Note 14e.

WARRANTY OBLIGATIONS (Tables)

12 Months Ended

Dec. 31, 2017

Product Warranties Disclosures [Abstract]

Schedule of warranty obligations

Changes in the Company’s product warranty liability for the year ended December 31, 2017, the six months ended December 31, 2016, and the year ended June 30, 2016 were as follows:

	December 31,						June 30,
	2017			2016			2016

Balance, at beginning of year	$	58,375		$	51,192		$	31,879
Additions and adjustments to cost of revenues		34,650			13,749			28,848
Usage and current warranty expenses		(14,214	)		(6,566	)		(9,535	)

Balance, at end of year		78,811			58,375			51,192
Less current portion		(14,785	)		(13,616	)		(14,114	)

Long term portion	$	64,026		$	44,759		$	37,078

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)

12 Months Ended

Dec. 31, 2017

Accumulated Other Comprehensive Income Loss Tables

Schedule of Changes in AOCI

The following table summarizes the changes in accumulated balances of other comprehensive income, net of taxes, for the year ended December 31, 2017:

	Unrealized gains (losses) on available-for-sale marketable securities			Unrealized gains (losses) on cash flow hedges			Unrealized gains (losses) on foreign currency translation			Total

Beginning balance	$	(136	)	$	19		$	(207	)	$	(324	)
Other comprehensive income (loss) before reclassifications		(297	)		975			29			707
Gains reclassified from accumulated other comprehensive income		-			(994	)		-			(994	)
Net current period other comprehensive income (loss)		(297	)		(19	)		29			(287	)

Ending balance	$	(433	)	$	-		$	(178	)	$	(611	)

The following table summarizes the changes in accumulated balances of other comprehensive loss, net of taxes, for the six months ended December 31, 2016:

	Unrealized gains (losses) on available-for-sale marketable securities			Unrealized gains (losses) on cash flow hedges			Unrealized gains (losses) on foreign currency translation			Total

Beginning balance	$	57		$	243		$	(29	)	$	271
Other comprehensive income (loss) before reclassifications		(193	)		93			(178	)		(278	)
Gains reclassified from accumulated other comprehensive income		-			(317	)		-			(317	)
Net current period other comprehensive loss		(193	)		(224	)		(178	)		(595	)

Ending balance	$	(136	)	$	19		$	(207	)	$	(324	)

The following table summarizes the changes in accumulated balances of other comprehensive income, net of taxes, for the year ended June 30, 2016:

	Unrealized gains (losses) on available-for-sale marketable securities		Unrealized gains (losses) on cash flow hedges			Unrealized gains (losses) on foreign currency translation			Total

Beginning balance	$	-	$	-		$	(222	)	$	(222	)
Other comprehensive income (loss) before reclassifications		56		412			193			661
Losses (gains) reclassified from accumulated other comprehensive income (loss)		1		(169	)		-			(168	)
Net current period other comprehensive income		57		243			193			493

Ending balance	$	57	$	243		$	(29	)	$	271

Schedule of Reclassifications out of AOCI

The following tables provides details about reclassifications out of accumulated other comprehensive income (loss):

Details about Accumulated Other Comprehensive Loss Components	Amount Reclassified from Accumulated Other Comprehensive Loss		Affected Line Item in the Statements of Operations
	Year ended
	December 31, 2017

Unrealized gains on cash flow hedges	$	166	Cost of revenues
		570	Research and development
		151	Sales and marketing
		153	General and administrative

		1,040	Total, before income taxes

		46	Income tax expense

	$	994	Total, net of income taxes

Unrealized gains on available-for-sale marketable securities	$	-	Financial income, net
		-	Income tax expense

	$	-	Total, net of income taxes

	$	994	Total, net of income taxes

Details about Accumulated Other Comprehensive Loss Components	Amount Reclassified from Accumulated Other Comprehensive Loss		Affected Line Item in the Statements of Operations
	Six months ended
	December 31, 2016

Unrealized gains on cash flow hedges	$	47	Cost of revenues
		227	Research and development
		58	Sales and marketing
		46	General and administrative

		378	Total, before income taxes

		61	Income tax expense

	$	317	Total, net of income taxes

Unrealized gains on available-for-sale marketable securities	$	-	Financial income, net
		-	Income tax expense

	$	-	Total, net of income taxes

	$	317	Total, net of income taxes

Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Item in the Statements of Operations
	Year ended
	June 30, 2016

Unrealized gains on cash flow hedges	$	30		Cost of revenues
		115		Research and development
		33		Sales and marketing
		24		General and administrative

		202		Total, before income taxes

		33		Income tax expense

	$	169		Total, net of income taxes

Unrealized losses on available-for-sale marketable securities	$	(1	)	Financial income, net
		-		Income tax expense

	$	(1	)	Total, net of income taxes

	$	168		Total, net of income taxes

DERIVATIVE INSTRUMENTS (Tables)

12 Months Ended

Dec. 31, 2017

Derivative Instruments Tables

Schedule of Derivative Instruments

The fair value of the Company’s outstanding derivative instruments is as follows:

	As of December 31,					As of June 30,
	2017			2016		2016

Derivative assets:
Derivatives not designated as cash flow hedging instruments:
Foreign exchange option contracts	$	221		$	-	$	214
Derivatives designated as cash flow hedging instruments:
Foreign exchange forward contracts		-			19		290

Total	$	221		$	19	$	504

Derivative liabilities:
Derivatives not designated as cash flow hedging instruments:
Foreign exchange option contracts	$	(285	)	$	-	$	(23	)
Foreign exchange forward contracts		(116	)		-		-

Total	$	(401	)	$	-	$	(23	)

Schedule of Change in Unrealized Gains (Losses)

The increase (decrease) in unrealized gains (losses) recognized in “accumulated other comprehensive income (loss)” on derivatives, net of tax effect, is as follows:

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Derivatives designated as cash flow hedging instruments:
Foreign exchange forward contracts	$	975	$	93	$	412	$	-

Total	$	975	$	93	$	412	$	-

Schedule of Net Gains (Losses) Reclassified

The net (gains) losses reclassified from “accumulated other comprehensive income (loss)” into income (loss), are as follows:

	Year ended December 31,		Six months ended December 31,			Year ended June 30,
	2017		2016			2016			2015

Derivatives designated as cash flow hedging instruments:
Foreign exchange forward contracts	$	994	$	(317	)	$	(169	)	$	-

Total	$	994	$	(317	)	$	(169	)	$	-

Commitments and Contingencies Disclosure [Abstract]

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84234895&loc=d3e41641-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
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+ Details

COMMITMENTS AND CONTINGENT LIABILITIES (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of future minimum lease commitments

2018		4,520
2019		3,801
2020		3,094
2021		2,512
2022		2,472
2023 and thereafter		6,934

	$	23,333

CONVERTIBLE PREFERRED STOCK (Tables)

12 Months Ended

Dec. 31, 2017

Temporary Equity Disclosure [Abstract]

Schedule of composition of convertible preferred stock

Composition of convertible preferred stock of the Company:

	Authorized						Issued and outstanding
	Number of shares
	December 31,				June 30,		December 31,				June 30,
	2017		2016		2016		2017		2016		2016

Stock of $0.0001 par value:
Preferred stock		95,000,000		95,000,000		95,000,000		-		-		-

Schedule of convertible preferred stock outstanding prior to consummation of IPO

	Shares outstanding		Number of shares of Common Stock issued upon conversion

Series A Preferred stock		15,558,830		5,186,276
Series B Preferred stock		18,760,196		6,253,398
Series C Preferred stock		15,984,655		5,328,217
Series D Preferred stock		16,024,251		5,341,416
Series D-1 Preferred stock		2,165,441		721,813
Series D-2 Preferred stock		2,598,528		866,175
Series D-3 Preferred stock		4,330,872		1,443,623
Series E Preferred stock		9,321,019		3,107,005
		84,743,792		28,247,923

STOCK CAPITAL (Tables)

12 Months Ended

Dec. 31, 2017

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of exercise price range of options

The options outstanding as of December 31, 2017, have been separated into exercise price ranges as follows:

		Options		Weighted		Options		Weighted
		outstanding		average		exercisable		average
Range of		as of		remaining		as of		remaining
exercise		December 31,		contractual		December 31,		contractual
price		2017		Life in years		2017		Life in years
$	0.87 - $1.50		202,281		1.44		202,281		1.44
$	1.68 - $2.46		660,264		3.68		660,264		3.68
$	3.03 - $5.01		1,778,547		6.81		1,263,352		6.79
$	9.36		15,267		7.08		8,949		7.08
$	13.70 – $14.85		438,430		9.12		78,309		9.02
$	15.34 – $17.14		193,571		8.61		60,314		8.49
$	20.81 - $25.09		235,950		7.57		132,900		7.49

			3,524,310		6.35		2,406,369		5.64

Schedule of recognized stock-based compensation expenses

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Cost of revenues	$	2,250	$	871	$	945	$	442
Research and development, net		5,703		2,061		2,364		635
Selling and marketing		5,387		1,852		2,915		809
General and administrative		4,224		1,816		2,820		1,070

Total stock-based compensation expense	$	17,564	$	6,600	$	9,044	$	2,956

Schedule of composition of common stock capital

Composition of common stock capital of the Company:

	Authorized						Issued and outstanding
	Number of shares
	December 31,				June 30,		December 31,				June 30,
	2017		2016		2016		2017		2016		2016

Stock of $0.0001 par value:
Common stock		125,000,000		125,000,000		125,000,000		43,812,601		41,259,391		40,889,922

Schedule of RSU Activity

A summary of the activity in the RSUs granted to employees and members of the board of directors for the year ended December 31, 2017, is as follows:

	No. of RSUs			Weighted average grant date fair value
Unvested as of January 1, 2017		1,515,018			19.74
Granted		1,252,815			27.30
Vested		(547,104	)		20.07
Forfeited		(132,737	)		18.65
Unvested as of December 31, 2017		2,087,992			24.33

Employee Stock Option [Member] | Employees and Members of Board of Directors [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary of the activity in the share options granted to employees and members of the board of directors

A summary of the activity in the share options granted to employees and members of the board of directors for the year ended December 31, 2017 and related information follows:

						Weighted
						average
				Weighted		remaining
	Number			average		contractual		Aggregate
	of			exercise		term		intrinsic
	options			price		in years		Value

Outstanding as of December 31, 2016		4,864,469			5.05		6.24		39,585
Granted		445,680			14.64
Exercised		(1,758,288	)		2.70
Forfeited or expired		(27,551	)		10.06
Outstanding as of December 31, 2017		3,524,310			7.40		6.35		106,251

Vested and expected to vest as of December 31, 2017		3,442,470			7.32		6.34		104,050

Exercisable as of December 31, 2017		2,406,369			5.58		5.64		76,931

Employee Stock Option [Member] | Nonemployee Consultants [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of exercise price range of options

The Company has granted options to purchase common shares and RSU’s to non-employee consultants as of December 31, 2017 as follows:

	Options & RSU’s
	outstanding				Exercisable
	as of				as of
Issuance	December 31,		Exercise		December 31,		Exercisable
Date	2017		price		2017		Through
October 24, 2012		2,000		2.46		2,000	October 24, 2022
January 27, 2014		1,144		3.51		713	January 27, 2024
May 1, 2014		2,000		3.51		1,875	May 1, 2024
September 17, 2014		6,498		3.96		5,509	September 17, 2024
October 29, 2014		2,668		5.01		224	October 29, 2024
August 19, 2015		10,439		0.00		-
November 8, 2015		1,449		0.00		-
April 18, 2016		1,250		0.00		-
July 11, 2016		1,501		0.00		-
September 21, 2016		4,000		15.34		250	September 21, 2026
September 21, 2016		3,813		0.00		-
March 15, 2017		7,000		0.00		-
March 15, 2017		7,500		13.70		500	March 15, 2027
March 27, 2017		4,000		0.00		-
November 20, 2017		6,000		0.00		-
December 26, 2017		2,667		0.00		667
		63,929				11,738

Schedule of deferred tax liabilities and assets

Tabular disclosure of an entity's stock, including par or stated value per share, number and dollar amount of share subscriptions, shares authorized, shares issued, shares outstanding, number and dollar amount of shares held in an employee trust, dividend per share, total dividends, share conversion features, par value plus additional paid in capital, the value of treasury stock and other information necessary to a fair presentation, and EPS information. Stock by class includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. Includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity. If more than one issue is outstanding, state the title of each issue and the corresponding dollar amount; dollar amount of any shares subscribed but unissued and the deduction of subscriptions receivable there from; number of shares authorized, issued, and outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21506-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.5-02(27))
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 14: http://www.xbrl.org/2003/role/presentationRef
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+ Details

INCOME TAXES (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Significant components of the Company’s deferred tax liabilities and assets are as follows:

	December 31,				June 30,
	2017		2016		2016

Assets in respect of:

Carryforward tax losses	$	-	$	-	$	4,186
Research and Development carryforward expenses- temporary differences		5,380		908		743
Stock based compensation		1,622		1,039		562
Other reserves		1,338		868		805

Deferred tax assets, net	$	8,340	$	2,815	$	6,296

Schedule of income (loss) before taxes

Income before taxes is comprised as follows:

	Year Ended December 31, 2017		Six months ended December 31, 2016		Year ended June 30,
	Year Ended December 31, 2017		Six months ended December 31, 2016		2016		2015

Domestic	$	7,461	$	3,165	$	3,758	$	2,830
Foreign		92,783		27,433		68,472		20,246

	$	100,244	$	30,598	$	72,230	$	23,076

Schedule of taxes on income

Taxes on income (tax benefit) are comprised as follows:

	Year ended December 31, 2017			Six months ended December 31, 2016		Year ended June 30,
	Year ended December 31, 2017			Six months ended December 31, 2016		2016			2015
Domestic taxes:
Current		19,889			1,047		1,737			1,655
Deferred		(42	)		507		(1,380	)		-
Foreign taxes:
Current		1,639			518		263			300
Deferred		(5,414	)		3,145		(4,999	)		-

	$	16,072		$	5,217	$	(4,379	)	$	1,955

Schedule of reconciliation between the theoretical tax expense and the actual tax expense (benefit)

	Year ended December 31,			Six months ended December 31,			Year ended June 30,
	2017			2016			2016			2015

Income before taxes, as reported in the consolidated statements of operations	$	100,244		$	30,598		$	72,230		$	23,076

Statutory tax rate		34	%		34	%		34	%		35	%
Theoretical tax benefits on the above amount at the US statutory tax rate		34,083			10,403			24,558			8,077
Income tax at rate other than the U.S. statutory tax rate		(34,734	)		(5,396	)		(30,229	)		(9,305	)
Tax Cuts and Jobs Act of 2017		18,735			-			-			-
Non-deductible expenses		(1,545	)		164			1,514			3,003
Other individually immaterial income tax items		(467	)		46			(222	)		180

Actual tax expense (tax benefit)	$	16,072		$	5,217		$	(4,379	)	$	1,955

FINANCIAL EXPENSES (INCOME), NET (Tables)

12 Months Ended

Dec. 31, 2017

Nonoperating Income (Expense) [Abstract]

Schedule of financial expenses (income), net

	Year ended December 31,			Six months ended December 31,			Year ended June 30,
	2017			2016			2016			2015

Remeasurement of warrants to purchase convertible preferred stock	$	-		$	-		$	-		$	5,350
Interest on term loan		-			-			-			579
Other financial expenses related to term loan		-			-			-			373
Expenses (income) related to hedging transaction		1,334			87			136			(1,721	)
Interest on short- term loan		-			-			-			316
Interest on marketable securities		(4,398	)		(1,504	)		(1,112	)		-
Amortization of marketable securities premium and accretion of discount, net		2,017			685			532			-
Exchange rate loss (income), net, bank charges and other finance expenses		(8,111	)		3,521			(27	)		180

	$	(9,158	)	$	2,789		$	(471	)	$	5,077

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA (Tables)

12 Months Ended

Dec. 31, 2017

Segment Reporting [Abstract]

Summary of revenues within geographic areas

The following is a summary of revenues within geographic areas:

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Revenues based on Customers’ location:
United States	$	348,949	$	160,321	$	334,260	$	238,340
Netherlands		70,067		23,099		36,377		21,349
Europe (*)		128,295		37,500		74,830		44,104
Rest of the World		59,734		19,077		44,376		21,285
Total revenues	$	607,045	$	239,997	$	489,843	$	325,078

(*) Except for Netherlands

Schedule of major customers data as percentage of total revenues

Major customer data as a percentage of total revenues:

	Year ended December 31,			Six months ended December 31,			Year ended June 30,
	2017			2016			2016			2015

Customer A		14.8	%		11.2	%		11.6	%		4.9	%
Customer B		8.1	%		8.4	%		10.1	%		5.4	%
Customer C		3.0	%		8.7	%		10.9	%		24.6	%

Summary of revenues by product family

The following is a summary of revenues by product family :

	Year ended December 31,		Six months ended December 31,		Year ended June 30,
	2017		2016		2016		2015

Inverters	$	290,632	$	112,585	$	223,756	$	156,984
Optimizers		286,856		115,229		244,852		158,513
Others		29,557		12,183		21,235		9,581
Total revenues	$	607,045	$	239,997	$	489,843	$	325,078

Schedule of long-lived assets by geographic region

Long-lived assets by geographic region:

	As of December 31,				As of June 30,
	2017		2016		2016

Israel	$	43,273	$	35,055	$	26,751
U.S.		567		515		518
Europe		1,219		466		508
China		5,985		36		31
Other		138		50		23

Total long-lived assets*	$	51,182	$	36,122	$	27,831

Long-lived assets are comprised of property and equipment, net (marketable securities, prepaid expenses, and lease deposits, intangible assets and deferred tax assets are not included).

GENERAL (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended	12 Months Ended
GENERAL (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015	Jun. 18, 2015
Organization Consolidation and Presentation of Financial Statements [Line Items]
Number of shares of common stock sold to the public	8,050,000
Number of shares of common stock sold pursuant to the full exercise of an overallotment option granted to the underwriters	1,050,000
Aggregate net proceeds received from offerings	$ 131,208
Convertible preferred stock converted into number of shares of common stock	28,247,923
Warrants to purchase number of shares of common stock	187,671					187,671
Amount of trade receivables offset against accounts payable			$ 3,180
Lender Concentration Risk [Member] \| Accounts Payable [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Percentage of customer revenue		61.00%	51.60%	69.00%
Customer Concentration Risk [Member] \| Sales Revenue, Net [Member]
Organization Consolidation and Presentation of Financial Statements [Line Items]
Percentage of customer revenue		11.20%	14.80%	32.50%	24.60%

SIGNIFICANT ACCOUNTING POLICIES (Narrative) (Details) € in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($) shares	Dec. 31, 2017 USD ($) shares	Jun. 30, 2016 USD ($) shares	Jun. 30, 2015 USD ($) shares	Dec. 31, 2017 EUR (€)	Jun. 30, 2016 EUR (€)
Financial statements in U.S. dollars
Accumulated other comprehensive income (loss) related to foreign currency translation adjustments, net	$ 207	$ 178	$ 29
Basic and Diluted Net Earnings Per Share
Total weighted average number of shares related to the outstanding stock options, convertible preferred stock and warrants to purchase convertible preferred stock, excluded from the calculation of diluted net earnings (loss) per share due to their anti-dilutive effect \| shares	374,156	197,516	16,208	20,565,747
Severance pay
Severance expenses	$ 1,131	$ 2,995	$ 1,761	$ 1,273
Shipping and handling costs
Shipping and handling costs	8,131	$ 29,693	21,922	26,931
Warranty obligations
Minimum term of warranty obligations for inverters		12 years
Minimum term of warranty obligations for power optimizers		25 years
Maximum extended product warranty period		25 years
Government grants
Government grants received				$ 763
Derivative financial instruments
Derivative instruments	5,098		17,693
Derivative assets	19	221	504
Derivative liability		$ 401	$ 23
Percentage of transaction value		90.00%
Accumulated effect retained earnings amount		$ 3,875
Euro Member Countries, Euro [Member]
Derivative financial instruments
Derivative instruments \| €					€ 54,000	€ 30,000

SIGNIFICANT ACCOUNTING POLICIES (Net Earnings (Loss) Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Numerator:
Net income	$ 25,381	$ 84,172	$ 76,609	$ 21,121
Dividends accumulated for the period				(17,550)
Net income available to shareholders of common stock	$ 25,381	$ 84,172	$ 76,609	$ 3,571
Denominator:
Shares used in computing net earnings per share of common stock, basic (shares)	41,026,926	42,209,238	39,987,935	11,902,911
Numerator:
Net income	$ 25,381	$ 84,172	$ 76,609	$ 21,121
Dividends accumulated for the period				(16,971)
Net income available to shareholders of common stock	$ 25,381	$ 84,172	$ 76,609	$ 4,150
Denominator:
Shares used in computing net earnings per share of common stock, basic	41,026,926	42,209,238	39,987,935	11,902,911
Effect of stock-based awards	2,812,416	3,216,069	4,388,140	3,366,537
Shares used in computing net earnings per share of common stock, diluted	43,839,342	45,425,307	44,376,075	15,269,448
Basic net income per share	$ 0.62	$ 1.99	$ 1.92	$ 0.30
Diluted net income per share	$ 0.58	$ 1.85	$ 1.73	$ 0.27

SIGNIFICANT ACCOUNTING POLICIES (Estimated Useful Lives of Property and Equipment) (Details)	12 Months Ended
	Dec. 31, 2017
Computers and peripheral equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	33.00%
Computers and peripheral equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	15.00%
Computers and peripheral equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	33.00%
Office furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	7.00%
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	10.00%
Machinery and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	7.00%
Machinery and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	20.00%
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	15.00%
Laboratory Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	15.00%
Laboratory Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	25.00%
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, depreciation rate	15.00%

SIGNIFICANT ACCOUNTING POLICIES (Concentrations of Credit risks) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016
Concentration Risk [Line Items]
Accrued allowance for doubtful accounts	$ 226	$ 128	$ 235
Rebate accrual	9,089	17,428	4,294
Amortized cost	118,950	180,974	111,514
Fair value	118,727	180,384	111,609
Net unrealized loss	$ 223	$ 590	$ 95
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Concentration Risk [Line Items]
Percentage of customer revenue	20.20%	35.20%	34.40%

SIGNIFICANT ACCOUNTING POLICIES (Estimate Fair Value of Stock Options and Warrants) (Details)	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Warrant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest					0.09%
Dividend yields					0.00%
Volatility					45.00%
Expected option term in years					1 year 2 months 16 days
Employee Stock Option [Member] \| Employee and Executive Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yields	0.00%	0.00%	0.00%	0.00%
Expected option term in years	6 years 22 days	6 years 22 days
Estimated forfeiture rate	0.00%	0.00%	10.30%
Employee Stock Option [Member] \| Employee and Executive Director [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest	1.28%	2.14%	1.39%	1.39%
Volatility	55.33%	58.08%	55.45%	46.50%
Expected option term in years			5 years 6 months	5 years 6 months
Estimated forfeiture rate				12.50%
Employee Stock Option [Member] \| Employee and Executive Director [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest	1.34%	2.17%	1.97%	2.06%
Volatility	55.34%	58.10%	56.03%	55.10%
Expected option term in years			6 years 1 month 10 days	6 years 3 months 7 days
Estimated forfeiture rate				18.70%
Employee Stock Option [Member] \| Nonemployee Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yields	0.00%	0.00%	0.00%	0.00%
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest	1.16%	2.12%	1.15%	1.59%
Volatility	55.33%	61.21%	55.37%	45.50%
Expected option term in years	6 years	6 years	6 years 4 months 24 days	7 years 4 months 24 days
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest	2.45%	2.42%	2.21%	2.58%
Volatility	58.57%	62.62%	55.75%	56.20%
Expected option term in years	10 years	10 years	10 years	10 years
Employee Stock Purchase Plan [Member] \| Employee and Executive Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest	0.60%		0.40%
Dividend yields	0.00%	0.00%	0.00%
Volatility	48.08%		62.84%
Expected option term in years	6 months	6 months	6 months	0 years
Employee Stock Purchase Plan [Member] \| Employee and Executive Director [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest		0.60%
Volatility		45.60%
Employee Stock Purchase Plan [Member] \| Employee and Executive Director [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest		1.07%
Volatility		48.08%

SIGNIFICANT ACCOUNTING POLICIES (Schedule of Change in Fair Value of Warrants) (Details) - USD ($)
$ in Thousands

6 Months Ended

12 Months Ended

Dec. 31, 2016

Dec. 31, 2017

Jun. 30, 2016

Jun. 30, 2015

Jun. 18, 2015

Mar. 31, 2015

Change in fair value of warrants to purchase convertible preferred stock

Balance at beginning of period

$ 765

Issuance of warrants to purchase preferred stock

Exercise of warrants to purchase common stock

^[1]

(6,115)

Change in fair value

5,350

Balance at end of period

Warrants to purchase number of shares of common stock

187,671

Cashless warrants exercised into common shares

154,768

Intrinsic value

$ 6,115

[1]	Upon the closing of the IPO, all outstanding warrants to purchase convertible preferred stock automatically converted into warrants to purchase 187,671 shares of common stock (See Note 1c).

MARKETABLE SECURITIES (Schedule of Available-For-Sale Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Available for-sale - matures within one year, amortized cost	$ 77,411	$ 74,511	$ 59,124
Available for-sale - matures within one year, gross unrealized gains	1	20	50
Available for-sale - matures within one year, gross unrealized losses	(148)	(66)	(11)
Available for-sale - matures within one year, fair value	77,264	74,465	59,163
Available for-sale - matures after one year, amortized cost	103,563	44,439	52,390
Available for-sale - matures after one year, gross unrealized gains		3	93
Available for-sale - matures after one year, gross unrealized losses	(443)	(180)	(37)
Available for-sale - matures after one year, fair value	103,120	44,262	52,446
Amortized cost	180,974	118,950	111,514
Gross unrealized gains	1	23	143
Gross unrealized losses	(591)	(246)	(48)
Fair value	180,384	118,727	111,609
Corporate bonds [Member]
Available for-sale - matures within one year, amortized cost	68,392	71,753	57,119
Available for-sale - matures within one year, gross unrealized gains	1	20	50
Available for-sale - matures within one year, gross unrealized losses	(121)	(54)	(11)
Available for-sale - matures within one year, fair value	68,272	71,719	57,158
Available for-sale - matures after one year, amortized cost	95,540	39,435	46,375
Available for-sale - matures after one year, gross unrealized gains		3	86
Available for-sale - matures after one year, gross unrealized losses	(380)	(159)	(31)
Available for-sale - matures after one year, fair value	95,160	39,279	46,430
Governmental bonds [Member]
Available for-sale - matures within one year, amortized cost	9,019	2,758	2,005
Available for-sale - matures within one year, gross unrealized gains
Available for-sale - matures within one year, gross unrealized losses	(27)	(12)
Available for-sale - matures within one year, fair value	8,992	2,746	2,005
Available for-sale - matures after one year, amortized cost	8,023	5,004	6,015
Available for-sale - matures after one year, gross unrealized gains			7
Available for-sale - matures after one year, gross unrealized losses	(63)	(21)	(6)
Available for-sale - matures after one year, fair value	$ 7,960	$ 4,983	$ 6,016

MARKETABLE SECURITIES (Schedule of Contractual Maturities) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Marketable Securities Schedule Of Contractual Maturities Details
Less than 12 months, Fair Value	$ 51,124	$ 72,269	$ 22,895
Less than 12 months, Gross unrealized losses	(66)	(148)	(11)
12 months or greater, Fair Value	39,373	103,116	20,070
12 months or greater, Gross unrealized losses	(180)	(443)	(37)
Maturities of available-for-sale marketable securities	$ 32,782	$ 80,269	$ 6,350

FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Money Market Funds [Member]
Fair value of assets	$ 6,163	$ 6,510	$ 13,373
Derivative Financial Instruments, Assets [Member]
Fair value of assets	(180)	19	481
Short-term corporate bonds [Member]
Fair value of assets	68,272	71,719	57,158
Short-term governmental bonds [Member]
Fair value of assets	8,992	2,746	2,005
Long-term corporate bonds [Member]
Fair value of assets	95,160	39,279	46,430
Long-term governmental bonds [Member]
Fair value of assets	7,960	4,983	6,016
Level 1 [Member] \| Money Market Funds [Member]
Fair value of assets	6,163	6,510	13,373
Level 1 [Member] \| Derivative Financial Instruments, Assets [Member]
Fair value of assets
Level 1 [Member] \| Short-term corporate bonds [Member]
Fair value of assets
Level 1 [Member] \| Short-term governmental bonds [Member]
Fair value of assets
Level 1 [Member] \| Long-term corporate bonds [Member]
Fair value of assets
Level 1 [Member] \| Long-term governmental bonds [Member]
Fair value of assets
Level 2 [Member] \| Money Market Funds [Member]
Fair value of assets
Level 2 [Member] \| Derivative Financial Instruments, Assets [Member]
Fair value of assets	(180)	19	481
Level 2 [Member] \| Short-term corporate bonds [Member]
Fair value of assets	68,272	71,719	57,158
Level 2 [Member] \| Short-term governmental bonds [Member]
Fair value of assets	8,992	2,746	2,005
Level 2 [Member] \| Long-term corporate bonds [Member]
Fair value of assets	95,160	39,279	46,430
Level 2 [Member] \| Long-term governmental bonds [Member]
Fair value of assets	7,960	4,983	6,016
Level 3 [Member] \| Money Market Funds [Member]
Fair value of assets
Level 3 [Member] \| Derivative Financial Instruments, Assets [Member]
Fair value of assets
Level 3 [Member] \| Short-term corporate bonds [Member]
Fair value of assets
Level 3 [Member] \| Short-term governmental bonds [Member]
Fair value of assets
Level 3 [Member] \| Long-term corporate bonds [Member]
Fair value of assets
Level 3 [Member] \| Long-term governmental bonds [Member]
Fair value of assets

PREPAID EXPENSES AND OTHER ACCOUNTS RECEIVABLE (Details) - USD ($)
$ in Thousands

Dec. 31, 2017

Dec. 31, 2016

Jun. 30, 2016

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Vendor non-trade receivables

^[1]

$ 33,719

$ 15,209

$ 15,375

Government authorities

3,421

2,585

2,727

Prepaid expenses and other

5,083

3,534

2,756

Foreign currency derivative contracts

482

Prepaid expenses and other accounts receivable

$ 42,223

$ 21,347

$ 21,340

[1]

Vendor non-trade receivables related to contract manufacturers derive from the sale of components to manufacturing vendors who manufacture products for the Company. The Company purchases these components directly from suppliers. The Company does not reflect the sale of these components in revenues (see also Note 14e).

INVENTORIES (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
INVENTORIES (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 10,053	$ 25,887	$ 9,805
Finished goods	57,310	57,105	71,745
Inventories	67,363	82,992	81,550
Write-down amount of inventory	$ 113	$ 1,352	$ 2,539	$ 992

PROPERTY AND EQUIPMENT AND INTANGIBLE ASSETS, NET (Details) - USD ($)
$ in Thousands

6 Months Ended

12 Months Ended

Dec. 31, 2016

Dec. 31, 2017

Jun. 30, 2016

Jun. 30, 2015

Less - accumulated depreciation

$ 49,343

$ 71,386

$ 38,965

13,221

20,204

11,134

Depreciated cost

^[1]

36,122

51,182

27,831

Depreciation expenses

2,702

7,011

3,763

$ 2,253

Purchase of intangible assets

600

800

Patent [Member]

Intangible asset, useful life

Original amount

1,400

800

Accumulated amortization

141

$ 285

10 years

Amortization of intangible assets

$ 144

Computers and peripheral equipment [Member]

Office furniture and equipment [Member]

6,053

9,872

5,190

Laboratory and testing equipment [Member]

1,505

1,785

1,289

Machinery and equipment [Member]

9,589

13,732

8,590

Property in progress under construction and development Cost

26,285

38,422

18,433

10,698

8,783

5,519

Leasehold improvements [Member]

5,898

7,536

5,450

Vehicles [Member]

Loss provision related to contractual inventory purchase obligations

$ 13

$ 39

$ 13

[1]	Long-lived assets are comprised of property and equipment, net (marketable securities, prepaid expenses and lease deposits, intangible assets and deferred tax assets are not included).

ACCRUED EXPENSES AND OTHER ACCOUNTS PAYABLE (Details) - USD ($)
$ in Thousands

Dec. 31, 2017

Dec. 31, 2016

Jun. 30, 2016

Payables and Accruals [Abstract]

Accrued expenses

$ 14,863

$ 4,209

$ 5,615

Government authorities

1,905

1,568

1,406

^[1]

1,627

2,009

2,834

Other

1,983

862

870

Accrued expenses and other accounts payable

$ 20,378

$ 8,648

$ 10,725

[1]	See also Note 14e.

WARRANTY OBLIGATIONS (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
WARRANTY OBLIGATIONS (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016
Changes in the Company's product warranty liability
Balance, at beginning of year	$ 51,192	$ 58,375	$ 31,879
Additions and adjustments to cost of revenues	13,749	34,650	28,848
Usage and current warranty expenses	(6,566)	(14,214)	(9,535)
Balance, at end of year	58,375	78,811	51,192
Less current portion	(13,616)	(14,785)	(14,114)
Long term portion	$ 44,759	$ 64,026	$ 37,078

TERM LOAN AND WARRANTS TO PURCHASE CONVERTIBLE PREFERRED STOCK (Details) $ / shares in Units, $ in Thousands		6 Months Ended	12 Months Ended
	Dec. 28, 2012 USD ($) $ / shares shares	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($) shares	Jun. 18, 2015 shares	Mar. 31, 2015 shares
Debt Instrument [Line Items]
Warrants granted to lender \| shares						187,671	187,671
Cashless warrants exercised into common shares \| shares					154,768
Cashless exercise of warrants to purchase common stock					$ 6,115
Term Loan [Member]
Debt Instrument [Line Items]
Loan amount	$ 10,000
Proceeds from loans	10,000
Loan transaction fee paid	$ 100
Debt instrument maturity period	42 months
Interest rate (as a percent)	11.90%
Number of monthly payments in which principal of loan to be paid	33
Term Loan [Member] \| Series D1 Preferred Stock [Member]
Debt Instrument [Line Items]
Warrants granted to lender \| shares	563,014
Exercise price of warrants (in dollars per share) \| $ / shares	$ 2.309
Period after a qualified initial public offering considered while deciding warrants exercisability	12 months

REVOLVING CREDIT LINE (Details) - Revolving Credit Facility [Member] - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
	Feb. 28, 2015	Feb. 17, 2015	Jun. 30, 2011	Dec. 31, 2017
Line of Credit Facility [Line Items]
Aggregate borrowings		$ 40,000	$ 20,000
Maximum specified percentage of eligible trade receivables considered for determining maximum borrowing capacity		80.00%	80.00%
Maximum specified percentage of inventories in transit considered for determining maximum borrowing capacity			65.00%
Maximum [Member]
Line of Credit Facility [Line Items]
Applicable margin (as a percent)	2.00%			2.75%
Minimum [Member]
Line of Credit Facility [Line Items]
Applicable margin (as a percent)	0.50%			0.75%

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Schedule of Changes in AOCI) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Beginning balance	$ 271	$ (324)	$ (222)
Other comprehensive income (loss) before reclassifications	(278)	707	661
Losses (gains) reclassified from accumulated other comprehensive income (loss)	(317)	(994)	(168)
Net current period other comprehensive income (loss)	(595)	(287)	493	$ (161)
Ending balance	(324)	(611)	271	(222)
Available-for-sale Securities [Member]
Beginning balance	57	(136)
Other comprehensive income (loss) before reclassifications	(193)	(297)	56
Losses (gains) reclassified from accumulated other comprehensive income (loss)			1
Net current period other comprehensive income (loss)	(193)	(297)	57
Ending balance	(136)	(433)	57
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Beginning balance	243	19
Other comprehensive income (loss) before reclassifications	93	975	412
Losses (gains) reclassified from accumulated other comprehensive income (loss)	(317)	(994)	(169)
Net current period other comprehensive income (loss)	(224)	(19)	243
Ending balance	19		243
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Beginning balance	(29)	(207)	(222)
Other comprehensive income (loss) before reclassifications	(178)	29	193
Losses (gains) reclassified from accumulated other comprehensive income (loss)
Net current period other comprehensive income (loss)	(178)	29	193
Ending balance	$ (207)	$ (178)	$ (29)	$ (222)

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Schedule of Reclassifications out of AOCI) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Cost of revenues	$ 159,097	$ 392,279	$ 337,887	$ 243,295
Research and development	20,279	54,966	33,231	22,018
Sales and marketing	20,444	50,032	34,833	24,973
General and administrative	6,790	18,682	12,133	6,535
Total, before income taxes	30,598	100,244	72,230	23,076
Income tax expense	5,217	16,072	(4,379)	1,955
Net income (loss)	25,381	84,172	76,609	21,121
Financial income (expenses), net	(2,789)	9,158	471	$ (5,077)
Total, net of income taxes	(317)	(994)	(168)
Cash Flow Hedging [Member] \| Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Cost of revenues	47	166	30
Research and development	227	570	115
Sales and marketing	58	151	33
General and administrative	46	153	24
Total, before income taxes	378	1,040	202
Income tax expense	61	46	33
Net income (loss)	317	994	169
Available-for-sale Securities [Member] \| Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Financial income (expenses), net			(1)
Income tax expense
Total, net of income taxes			(1)
Total, net of income taxes	$ 317	$ 994	$ 168

DERIVATIVE INSTRUMENTS (Schedule of Fair Value of Derivative Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Derivative assets	$ 221	$ 19	$ 504
Derivative liabilities	(401)		(23)
Option Contract [Member]
Derivative assets	221		214
Derivative liabilities	(285)		(23)
Forward Contract [Member]
Derivative assets		19	290
Derivative liabilities	$ (116)

DERIVATIVE INSTRUMENTS (Schedule of Change in Unrealized Gains (Losses)) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Derivative Instruments Schedule Of Change In Unrealized Gains Losses Details
Derivatives designated as cash flow hedging instruments: Foreign exchange forward contracts	$ 93	$ 975	$ 412
Total	$ 93	$ 975	$ 412

DERIVATIVE INSTRUMENTS (Schedule of Net Gains (Losses) Reclassified) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Derivative Instruments Schedule Of Net Gains Losses Reclassified Details
Derivatives designated as cash flow hedging instruments: Foreign exchange forward contracts	$ (317)	$ 994	$ (169)
Total	(317)	994	(169)
Expenses (income) related to hedging transaction	$ 87	$ (1,334)	$ 136	$ (1,721)

COMMITMENTS AND CONTINGENT LIABILITIES (Schedule of Future Minimum Lease Commitments) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Future minimum lease commitments
2018	$ 4,520
2019	3,801
2020	3,094
2021	2,512
2022	2,472
2023 and thereafter	6,934
Future minimum lease commitments amount	$ 23,333

COMMITMENTS AND CONTINGENT LIABILITIES (Narrative) (Lease Commitments) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Lease commitments
Contract term		10 years
Rent expenses	$ 1,199	$ 3,449	$ 2,238	$ 1,714

COMMITMENTS AND CONTINGENT LIABILITIES (Narrative) (Guarantees) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Office Rent Lease Agreements [Member]
Guarantor Obligations [Line Items]
Guarantees amount	$ 1,191
Customs Transactions [Member]
Guarantor Obligations [Line Items]
Guarantees amount	58
Credit Card Limits [Member]
Guarantor Obligations [Line Items]
Guarantees amount	$ 184

COMMITMENTS AND CONTINGENT LIABILITIES (Narrative) (Contractual Obligations) (Details) - USD ($)
$ in Thousands

6 Months Ended

12 Months Ended

Dec. 31, 2016

Dec. 31, 2017

Jun. 30, 2016

Governmental commitments

Royalties payment percentage to IIA for first three years

4.00%

Royalties percentage of 4% for number of years

3 years

Royalties payment percentage to IIA for thereafter years

4.50%

Maximum royalties percentage of grants received

100.00%

Governmental commitments amount

$ 1,022

Research and development grants received from IIA

990

Accumulated interest

Royal expense realted to IIA grants

260

$ 748

Contractual purchase obligations

Non-cancelable purchase obligations

196,222

Provision for contractual inventory purchase obligations

^[1]

$ 2,009

1,627

$ 2,834

Capital expenditures

$ 23,263

[1]	See also Note 14e.

LEASE INCENTIVE OBLIGATION (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Leases [Abstract]
Received in cash from the Lessor	$ 2,938
Operating lease receivable	2,049
Operating lease receivable, noncurrent	$ 1,765

CONVERTIBLE PREFERRED STOCK (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended
	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 30, 2015
Temporary Equity [Line Items]
Classification of convertible preferred stock temporary equity into stockholders' equity (deficiency)	$ 140,915
Series A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					15,558,830
Number of Shares of Common Stock issued upon conversion					5,186,276
Series B Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					18,760,196
Number of Shares of Common Stock issued upon conversion					6,253,398
Series C Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					15,984,655
Number of Shares of Common Stock issued upon conversion					5,328,217
Series D Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					16,024,251
Number of Shares of Common Stock issued upon conversion					5,341,416
Series D1 Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					2,165,441
Number of Shares of Common Stock issued upon conversion					721,813
Series D2 Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					2,598,528
Number of Shares of Common Stock issued upon conversion					866,175
Series D3 Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					4,330,872
Number of Shares of Common Stock issued upon conversion					1,443,623
Series E Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Outstanding, Number of shares					9,321,019
Number of Shares of Common Stock issued upon conversion					3,107,005
Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Authorized, Number of shares		95,000,000	95,000,000	95,000,000
Issued, Number of shares
Outstanding, Number of shares					84,743,792
Number of Shares of Common Stock issued upon conversion					28,247,923
Convertible preferred stock, par value		$ 0.0001	$ 0.0001	$ 0.0001

STOCK CAPITAL (Common Stock) (Details)	12 Months Ended
STOCK CAPITAL (Common Stock) (Details)	Dec. 31, 2017 item $ / shares shares	Dec. 31, 2016 $ / shares shares	Jun. 30, 2016 $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Reverse stock split ratio	3
Common stock capital
Par value \| $ / shares	$ 0.0001	$ 0.0001	$ 0.0001
Authorized	125,000,000	125,000,000	125,000,000
Common stock, issued shares	43,812,601	41,259,391	40,889,922
Common stock, outstanding shares	43,812,601	41,259,391	40,889,922
Number of votes per share \| item	1

STOCK CAPITAL (Stock option plans) (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved for issuance pursuant to stock awards under the plan		10,000,000
Unrecognized compensation expense		$ 56,867
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options available for future grant under the plan		379,358
Employee Stock Option [Member] \| Employees and Members of Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised	$ 1,790	$ 44,625	$ 30,670
Weighted average grant date fair values options granted to employees and executive directors	$ 8.86	$ 7.94	$ 13.27	$ 4.24
Employee Stock Option [Member] \| 2015 Global Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved for issuance pursuant to stock awards under the plan		5,890,087
Number of options available for future grant under the plan		2,003,126
Percentage of common shares increase automatically each year		5.00%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved for issuance pursuant to stock awards under the plan		1,301,154
Number of options available for future grant under the plan		1,032,777
Number of Common stock purchased		268,377
Period of plan increase automatically number of shares		487,643
Percentage of common shares increase automatically each year		1.00%
Maximum percentage of salary		10.00%
Aggregate limit per participant		$ 10
Purchase price of common stock, percent		85.00%

STOCK CAPITAL (Summary of the activity in the share options) (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016
Aggregate intrinsic Value
Outstanding at the beginning of the period			$ 6,115
Outstanding at the end of the period
Employee Stock Option [Member] \| Employees and Members of Board of Directors [Member]
Number of options
Outstanding at the beginning of the period		4,864,469
Granted		445,680
Exercised		(1,758,288)
Forfeited or expired		(27,551)
Outstanding at the end of the period	4,864,469	3,524,310
Weighted average exercise price
Outstanding at the beginning of the period		$ 5.05
Granted		14.64
Exercised		2.70
Forfeited or expired		10.06
Outstanding at the end of the period	$ 5.05	$ 7.40
Weighted average remaining contractual term in years
Outstanding	6 years 2 months 27 days	6 years 4 months 6 days
Aggregate intrinsic Value
Outstanding at the beginning of the period		$ 39,585
Outstanding at the end of the period	$ 39,585	$ 106,251
Vested and expected to vest at the end of the period
Number of options		3,442,470
Weighted average exercise price		$ 7.32
Weighted average remaining contractual term in years		6 years 4 months 2 days
Aggregate intrinsic Value		$ 104,050
Exercisable at the end of the period
Number of options		2,406,369
Weighted average exercise price		$ 5.58
Weighted average remaining contractual term in years		5 years 7 months 21 days
Aggregate intrinsic Value		$ 76,931

STOCK CAPITAL (Schedule of exercise price ranges) (Details) - Employees and Members of Board of Directors [Member]	12 Months Ended
	Dec. 31, 2017 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding	3,524,310
Weighted average remaining contractual Life in years	6 years 4 months 6 days
Options exercisable	2,406,369
Weighted average remaining contractual Life in years	5 years 7 months 21 days
Exercise Price Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise price, lower \| $ / shares	$ 0.87
Range of exercise price, upper \| $ / shares	$ 1.50
Options outstanding	202,281
Weighted average remaining contractual Life in years	1 year 5 months 9 days
Options exercisable	202,281
Weighted average remaining contractual Life in years	1 year 5 months 9 days
Exercise Price Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise price, lower \| $ / shares	$ 1.68
Range of exercise price, upper \| $ / shares	$ 2.46
Options outstanding	660,264
Weighted average remaining contractual Life in years	3 years 8 months 5 days
Options exercisable	660,264
Weighted average remaining contractual Life in years	3 years 8 months 5 days
Exercise Price Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise price, lower \| $ / shares	$ 3.03
Range of exercise price, upper \| $ / shares	$ 5.01
Options outstanding	1,778,547
Weighted average remaining contractual Life in years	6 years 9 months 22 days
Options exercisable	1,263,352
Weighted average remaining contractual Life in years	6 years 9 months 14 days
Exercise Price Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price \| $ / shares	$ 9.36
Options outstanding	15,267
Weighted average remaining contractual Life in years	7 years 29 days
Options exercisable	8,949
Weighted average remaining contractual Life in years	7 years 29 days
Exercise Price Range Five [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise price, lower \| $ / shares	$ 13.70
Range of exercise price, upper \| $ / shares	$ 14.85
Options outstanding	438,430
Weighted average remaining contractual Life in years	9 years 1 month 13 days
Options exercisable	78,309
Weighted average remaining contractual Life in years	9 years 7 days
Exercise Price Range Six [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise price, lower \| $ / shares	$ 15.34
Range of exercise price, upper \| $ / shares	$ 17.14
Options outstanding	193,571
Weighted average remaining contractual Life in years	8 years 7 months 10 days
Options exercisable	60,314
Weighted average remaining contractual Life in years	8 years 5 months 27 days
Exercise Price Range Seven [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise price, lower \| $ / shares	$ 20.81
Range of exercise price, upper \| $ / shares	$ 25.09
Options outstanding	235,950
Weighted average remaining contractual Life in years	7 years 6 months 25 days
Options exercisable	132,900
Weighted average remaining contractual Life in years	7 years 5 months 27 days

STOCK CAPITAL (Schedule of RSU Activity) (Details)	12 Months Ended
STOCK CAPITAL (Schedule of RSU Activity) (Details)	Dec. 31, 2017 $ / shares shares
Stock Capital Schedule Of Rsu Activity Details
Unvested at beginning of period \| shares	1,515,018
Granted \| shares	1,252,815
Vested \| shares	(547,104)
Forfeited \| shares	(132,737)
Unvested at end of period \| shares	2,087,992
Unvested at beginning of period, grant date fair value \| $ / shares	$ 19.74
Granted \| $ / shares	27.30
Vested \| $ / shares	20.07
Forfeited \| $ / shares	18.65
Unvested at end of period, grant date fair value \| $ / shares	$ 24.33

STOCK CAPITAL (Options issued to non-employee consultants) (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expenses	$ 6,600	$ 17,564	$ 9,044	$ 2,956
Employee Stock Option [Member] \| Nonemployee Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		63,929
Exercisable at the end of the period		11,738
Stock compensation expenses	$ 66	$ 986	$ 524	$ 563
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		2,000
Exercise price		$ 2.46
Exercisable at the end of the period		2,000
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		1,144
Exercise price		$ 3.51
Exercisable at the end of the period		713
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		2,000
Exercise price		$ 3.51
Exercisable at the end of the period		1,875
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		6,498
Exercise price		$ 3.96
Exercisable at the end of the period		5,509
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		2,668
Exercise price		$ 5.01
Exercisable at the end of the period		224
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Six [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		10,439
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Seven [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		1,449
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Eight [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		1,250
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Nine [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		1,501
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Ten [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		4,000
Exercise price		$ 15.34
Exercisable at the end of the period		250
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Eleven [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		3,813
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Twelve [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		7,000
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Thirteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		7,500
Exercise price		$ 13.70
Exercisable at the end of the period		500
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Fourteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		4,000
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		6,000
Exercise price		$ 0.00
Exercisable at the end of the period
Employee Stock Option [Member] \| Nonemployee Consultants [Member] \| Award Date Sixteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at the end of the period		2,667
Exercise price		$ 0.00
Exercisable at the end of the period		667

STOCK CAPITAL (Schedule of stock-based compensation expense for employees and non-employee consultants) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 6,600	$ 17,564	$ 9,044	$ 2,956
Cost of Sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	871	2,250	945	442
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	2,061	5,703	2,364	635
Selling and Marketing Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	1,852	5,387	2,915	809
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 1,816	$ 4,224	$ 2,820	$ 1,070

INCOME TAXES (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
INCOME TAXES (Narrative) (Details) - USD ($)	Dec. 22, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Income Taxes [Line Items]
Corporate tax rate (as a percent)			34.00%		34.00%	34.00%	35.00%
Additional income tax expense		$ 19,200,000
Expected to reverse amount in future for income tax	$ 500,000
One-time transition tax for foreign earnings	18,700,000
One-time transition tax for cumulative foreign earnings	$ 145,000,000
Decrease in deferred tax assets					$ 500,000
Unrecognized tax benefits		$ 600,000	$ 300,000		$ 600,000
ISRAEL \| Subsidiaries [Member]
Income Taxes [Line Items]
Corporate tax rate (as a percent)					24.00%	25.00%	26.50%	26.50%
Tax exempt profits					$ 151,000,000
ISRAEL \| Subsidiaries [Member] \| Subsequent Event [Member]
Income Taxes [Line Items]
Corporate tax rate (as a percent)				23.00%
GERMANY \| Subsidiaries [Member]
Income Taxes [Line Items]
Corporate tax rate (as a percent)					33.00%

INCOME TAXES (Schedule of Deferred Tax Liabilities And Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Assets in respect of:
Carryforward tax losses			$ 4,186
Research and Development carryforward expenses- temporary differences	5,380	908	743
Stock based compensation	1,622	1,039	562
Other reserves	1,338	868	805
Deferred tax assets, net	$ 8,340	$ 2,815	$ 6,296

INCOME TAXES (Schedule of Income (Loss) Before Taxes) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Domestic	$ 3,165	$ 7,461	$ 3,758	$ 2,830
Foreign	27,433	92,783	68,472	20,246
Income (loss) before taxes on income	$ 30,598	$ 100,244	$ 72,230	$ 23,076

INCOME TAXES (Schedule of Taxes on Income) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Domestic taxes:
Current	$ 1,047	$ 19,889	$ 1,737	$ 1,655
Deferred	507	(42)	(1,380)
Foreign taxes:
Current	518	1,639	263	300
Deferred	3,145	(5,414)	(4,999)
Actual tax expense (tax benefit)	$ 5,217	$ 16,072	$ (4,379)	$ 1,955

INCOME TAXES (Schedule of reconciliation between the theoretical tax expense and the actual tax expense (benefit)) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Income before taxes, as reported in the consolidated statements of operations	$ 30,598	$ 100,244	$ 72,230	$ 23,076
Statutory tax rate	34.00%	34.00%	34.00%	35.00%
Theoretical tax benefits on the above amount at the US statutory tax rate	$ 10,403	$ 34,083	$ 24,558	$ 8,077
Income tax at rate other than the U.S. statutory tax rate	(5,396)	(34,734)	(30,229)	(9,305)
Tax Cuts and Jobs Act of 2017		18,735
Non-deductible expenses	164	(1,545)	1,514	3,003
Other individually immaterial income tax items	46	(467)	(222)	180
Actual tax expense (tax benefit)	$ 5,217	$ 16,072	$ (4,379)	$ 1,955

FINANCIAL EXPENSES (INCOME), NET (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Nonoperating Income (Expense) [Abstract]
Remeasurement of warrants to purchase convertible preferred stock				$ 5,350
Interest on term loan				579
Other financial expenses related to term loan				373
Expenses (income) related to hedging transaction	87	1,334	136	(1,721)
Interest on short-term loan				316
Interest on marketable securities	(1,504)	(4,398)	(1,112)
Amortization of marketable securities premium and accretion of discount, net	685	2,017	532
Exchange rate loss (income), net, bank charges and other finance expenses	3,521	(8,111)	(27)	180
Financial expenses (income), net	$ 2,789	$ (9,158)	$ (471)	$ 5,077

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA (Summary of Revenues Within Geographic Areas) (Details)
$ in Thousands

6 Months Ended

12 Months Ended

Dec. 31, 2016

USD ($)

Dec. 31, 2017

USD ($)

item

Jun. 30, 2016

USD ($)

Jun. 30, 2015

USD ($)

Revenues from External Customers and Long-Lived Assets [Line Items]

Number of reportable segments | item

Revenues from External Customers and Long-Lived Assets [Line Items]

$ 239,997

$ 607,045

$ 489,843

$ 325,078

UNITED STATES

Revenues from External Customers and Long-Lived Assets [Line Items]

160,321

348,949

334,260

238,340

NETHERLANDS

Revenues from External Customers and Long-Lived Assets [Line Items]

23,099

70,067

36,377

21,349

Europe [Member]

Revenues from External Customers and Long-Lived Assets [Line Items]

^[1]

37,500

128,295

74,830

44,104

Others [Member]

Revenues from External Customers and Long-Lived Assets [Line Items]

$ 19,077

$ 59,734

$ 44,376

$ 21,285

[1]	Except for Germany

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA (Schedule of Major Customers Data As a Percentage of Total Revenues) (Details) - Sales Revenue, Goods, Net [Member] - Customer Concentration Risk [Member]	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Customer A [Member]
Revenue, Major Customer [Line Items]
Percentage of customer revenue	11.20%	14.80%	11.60%	4.90%
Customer B [Member]
Revenue, Major Customer [Line Items]
Percentage of customer revenue	8.40%	8.10%	10.10%	5.40%
Customer C [Member]
Revenue, Major Customer [Line Items]
Percentage of customer revenue	8.70%	3.00%	10.90%	24.60%

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA (Summary of Revenues by Product Family) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Revenue from External Customer [Line Items]
Total revenues	$ 239,997	$ 607,045	$ 489,843	$ 325,078
Inverters [Member]
Revenue from External Customer [Line Items]
Total revenues	112,585	290,632	223,756	156,984
Optimizers [Member]
Revenue from External Customer [Line Items]
Total revenues	115,229	286,856	244,852	158,513
Other Products [Member]
Revenue from External Customer [Line Items]
Total revenues	$ 12,183	$ 29,557	$ 21,235	$ 9,581

GEOGRAPHIC INFORMATION AND MAJOR CUSTOMER AND PRODUCT DATA (Schedule of Long-Lived Assets by Geographic Region) (Details) - USD ($)
$ in Thousands

Dec. 31, 2017

Dec. 31, 2016

Jun. 30, 2016

Revenues from External Customers and Long-Lived Assets [Line Items]

^[1]

$ 51,182

$ 36,122

$ 27,831

ISRAEL

Revenues from External Customers and Long-Lived Assets [Line Items]

43,273

35,055

26,751

UNITED STATES

Revenues from External Customers and Long-Lived Assets [Line Items]

567

515

518

Europe [Member]

Revenues from External Customers and Long-Lived Assets [Line Items]

1,219

466

508

China [Member]

Revenues from External Customers and Long-Lived Assets [Line Items]

5,985

Others [Member]