Short-term Investments - Additional Information (Detail) - US Treasury Securities - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Summary Of Investment Holdings [Line Items]
Available-for-sale securities, amortized cost	$ 109,200	$ 108,800
Available-for-sale securities, fair value	109,900	108,900
Available-for-sale securities, unrealized loss position	$ 0	$ 0

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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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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