Fair Value Measurements - Available For Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair value of available for sale marketable securities
Amortized Cost	$ 45,166	$ 72,799
Gross Unrealized Gains	73	37
Gross Unrealized Losses	(30)	(8)
Fair Value	45,209	72,828
U.S. Treasury securities
Fair value of available for sale marketable securities
Amortized Cost	2,005	7,019
Gross Unrealized Gains	11	4
Fair Value	2,016	7,023
U.S. Government agency securities
Fair value of available for sale marketable securities
Amortized Cost	9,851	17,701
Gross Unrealized Gains	50	16
Fair Value	9,901	17,717
Corporate debt obligations
Fair value of available for sale marketable securities
Amortized Cost	33,310	48,079
Gross Unrealized Gains	12	17
Gross Unrealized Losses	(30)	(8)
Fair Value	$ 33,292	$ 48,088

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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