Fair Value of Financial Assets and Liabilities - Summary of Gross Unrealized Gains and Losses of Marketable Securities (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 52,299
Gross Unrealized Gains	18
Gross Unrealized Losses	(2)
Fair Value	52,315
U.S. Government Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	16,791
Gross Unrealized Gains	6
Fair Value	16,797
U.S. Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	14,050
Gross Unrealized Gains	12
Gross Unrealized Losses	(2)
Fair Value	14,060
Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	21,458
Fair Value	$ 21,458

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).

+ References

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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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