Fair Value Measurements - Schedule of Available-for-sale Investments (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Gross Amortized Cost	$ 38,057	$ 14,730
Gross Unrealized Gains		7
Gross Unrealized Losses	(7)
Market Value	38,050	14,737
Short-term Investments [Member] \| Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross Amortized Cost	18,183	5,491
Gross Unrealized Gains		3
Market Value	18,183	5,494
Short-term Investments [Member] \| Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross Amortized Cost	1,008	2,218
Gross Unrealized Gains		1
Market Value	1,008	2,219
Short-term Investments [Member] \| Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross Amortized Cost	18,866	7,021
Gross Unrealized Gains		3
Gross Unrealized Losses	(7)
Market Value	$ 18,859	$ 7,024

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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