Marketable Securities (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 21,985
Gross Unrealized Losses	(5)
Fair Value	21,980
Asset-backed securities [Member] \| Asset-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,999
Gross Unrealized Losses	(2)
Fair Value	4,997
Corporate debt securities [Member] \| Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	16,986
Gross Unrealized Losses	(3)
Fair Value	$ 16,983

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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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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