MARKETABLE SECURITIES - Schedule of Current Available-for-Sale Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Schedule of Available-for-sale Marketable Securities
Amortized Cost	$ 119,740	$ 4,995
Gross Unrealized Gains	6	0
Gross Unrealized Losses	0	0
Available-for-sale marketable debt securities	119,746	4,995
Treasury discount notes
Schedule of Available-for-sale Marketable Securities
Amortized Cost	99,795
Gross Unrealized Gains	6
Gross Unrealized Losses	0
Available-for-sale marketable debt securities	99,801
Commercial paper
Schedule of Available-for-sale Marketable Securities
Amortized Cost	19,945	4,995
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Available-for-sale marketable debt securities	$ 19,945	$ 4,995

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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