Investment Securities - Summary of Available-For-Sale Investment Securities Held by the Company (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	$ 44,224	$ 77,918
Available-for-sale investment securities, Gross Unrealized Gains	128	152
Available-for-sale investment securities, Gross Unrealized Losses	(1)	(4)
Available-for-sale investment securities, Fair Market Value	44,351	78,066
U.S. Government and Agency Obligations
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	29,984	43,275
Available-for-sale investment securities, Gross Unrealized Gains	32	94
Available-for-sale investment securities, Gross Unrealized Losses	(1)	(1)
Available-for-sale investment securities, Fair Market Value	30,015	43,368
Certificates of Deposit
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	5,743	5,931
Available-for-sale investment securities, Gross Unrealized Gains	57	51
Available-for-sale investment securities, Fair Market Value	5,800	5,982
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	2,998	17,645
Available-for-sale investment securities, Fair Market Value	2,998	17,645
Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investment securities, Amortized Cost	5,499	11,067
Available-for-sale investment securities, Gross Unrealized Gains	39	7
Available-for-sale investment securities, Gross Unrealized Losses		(3)
Available-for-sale investment securities, Fair Market Value	$ 5,538	$ 11,071

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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