Marketable Securities - Schedule of Available-for-sale Marketable Securities and Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Cash and cash equivalents:
Amortized Cost Value	$ 109,559	$ 91,436
Fair Value	109,559	91,436
Marketable securities:
Amortized Cost Value		23,259
Gross Unrealized Gains		23
Gross Unrealized Losses		(2)
Fair Value		23,280
Cash
Cash and cash equivalents:
Amortized Cost Value	39,309	44,616
Fair Value	39,309	44,616
Money market funds
Cash and cash equivalents:
Amortized Cost Value	70,250	46,820
Fair Value	$ 70,250	46,820
Domestic corporate debt securities
Marketable securities:
Amortized Cost Value		18,266
Gross Unrealized Gains		21
Gross Unrealized Losses		(2)
Fair Value		18,285
Domestic corporate commercial paper
Marketable securities:
Amortized Cost Value		4,993
Gross Unrealized Gains		2
Gross Unrealized Losses		0
Fair Value		$ 4,995

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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