Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	$ 61,532	$ 58,124
Marketable securities, Unrealized Gains	159	159
Marketable securities, Unrealized Losses	(369)	(32)
Marketable securities, Aggregate Fair Value	61,322	58,251
Cash and cash equivalents	9,302	11,965
Less: Cash equivalents	(3,943)	(6,399)
Short-Term Marketable Securities
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	18,048	16,263
Marketable securities, Unrealized Gains	31	43
Marketable securities, Unrealized Losses	(51)	(2)
Marketable securities, Aggregate Fair Value	18,028	16,304
Short-Term Marketable Securities \| Money Market Accounts
Schedule Of Available For Sale Securities [Line Items]
Cash and cash equivalents	3,943	4,700
Cash and cash equivalents fair value disclosure	3,943	4,700
Short-Term Marketable Securities \| Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	18,048	17,962
Marketable securities, Unrealized Gains	31	43
Marketable securities, Unrealized Losses	(51)	(2)
Marketable securities, Aggregate Fair Value	18,028	18,003
Long-Term Marketable Securities
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	43,484	41,861
Marketable securities, Unrealized Gains	128	116
Marketable securities, Unrealized Losses	(318)	(30)
Marketable securities, Aggregate Fair Value	43,294	41,947
Long-Term Marketable Securities \| U.S. Government Agency Securities
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	1,000
Marketable securities, Unrealized Gains	3
Marketable securities, Aggregate Fair Value	1,003
Long-Term Marketable Securities \| Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Marketable securities, Amortized Cost Basis	42,484	41,861
Marketable securities, Unrealized Gains	125	116
Marketable securities, Unrealized Losses	(318)	(30)
Marketable securities, Aggregate Fair Value	$ 42,291	$ 41,947

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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