Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 3,017	$ 6,684
Unrealized Gains	0	0
Unrealized Losses	(1)	(5)
Estimated Fair Value	3,016	6,679
Corporate Debt Securities with 1 Year or Less Maturity
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	3,017	3,612
Unrealized Gains	0	0
Unrealized Losses	(1)	(2)
Estimated Fair Value	3,016	3,610
Corporate Debt Securities with 1 to 2 Years Maturity
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	0	3,072
Unrealized Gains	0	0
Unrealized Losses	0	(3)
Estimated Fair Value	$ 0	$ 3,069

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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