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Available-for-Sale Securities - Summary of Available-for-Sale Securities Held (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 120,236	$ 67,923
Gross unrealized gains	8	16
Gross unrealized losses	(53)	(2)
Fair Value	120,191	67,937
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	106,298	40,467
Gross unrealized gains	8	11
Gross unrealized losses	(29)	(1)
Fair Value	106,277	40,477
Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	5,876	18,634
Gross unrealized gains		4
Gross unrealized losses	(3)	(1)
Fair Value	5,873	18,637
U.S. Government Agency Securities and Treasuries
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	8,062	8,822
Gross unrealized gains		1
Gross unrealized losses	(21)
Fair Value	$ 8,041	$ 8,823

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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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