Marketable Debt Securities - Schedule of Marketable Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Marketable Securities [Line Items]
Amortized Cost	$ 23,077	$ 62,358
Unrealized Losses		(7)
Unrealized Gains	83	30
Fair Value	23,160	62,381
Asset Backed Securities
Marketable Securities [Line Items]
Amortized Cost	14,639	19,589
Unrealized Losses		(1)
Unrealized Gains	50	10
Fair Value	14,689	19,598
Corporate Debt Securities
Marketable Securities [Line Items]
Amortized Cost	5,700	19,387
Unrealized Losses		(3)
Unrealized Gains	22	9
Fair Value	5,722	19,393
Commercial Paper
Marketable Securities [Line Items]
Amortized Cost	2,738	17,882
Unrealized Gains	11	11
Fair Value	$ 2,749	17,893
US Government Agency Bonds
Marketable Securities [Line Items]
Amortized Cost		5,500
Unrealized Losses		(3)
Fair Value		$ 5,497

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).

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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).

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