Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 0	$ 21,985
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(5)
Fair Value	0	21,980
Asset-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	4,999
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(2)
Fair Value	0	4,997
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	16,986
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(3)
Fair Value	$ 0	$ 16,983

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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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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