Fair Value Measurements - Available For Sale (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair value of available for sale marketable securities
Amortized Cost	$ 72,799	$ 75,435
Gross Unrealized Gains	37
Gross Unrealized Losses	(8)	(34)
Fair Value	72,828	75,401
U.S. Treasury securities
Fair value of available for sale marketable securities
Amortized Cost	7,019
Gross Unrealized Gains	4
Fair Value	7,023
U.S. Government agency securities
Fair value of available for sale marketable securities
Amortized Cost	17,701	49,124
Gross Unrealized Gains	16
Gross Unrealized Losses		(27)
Fair Value	17,717	49,097
Corporate debt obligations
Fair value of available for sale marketable securities
Amortized Cost	48,079	26,311
Gross Unrealized Gains	17
Gross Unrealized Losses	(8)	(7)
Fair Value	$ 48,088	$ 26,304

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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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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