Investments - Summary of Gross Unrealized Gains and Losses and Credit Losses (Detail) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 378,488	$ 423,153
Gross Unrealized Gains	224	397
Gross Unrealized Losses	(82)	(153)
Fair Value	378,630	423,397
U.S. Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	17,917	36,444
Gross Unrealized Gains	3	18
Gross Unrealized Losses	(4)	(5)
Fair Value	17,916	36,457
U.S. Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	253,296	268,841
Gross Unrealized Gains	174	305
Gross Unrealized Losses	(56)	(133)
Fair Value	253,414	269,013
International Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	51,911	52,411
Gross Unrealized Gains	42	65
Gross Unrealized Losses	(22)	(15)
Fair Value	51,931	52,461
U.S. Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	19,824	30,373
Fair Value	19,824	30,373
International Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	28,358	24,144
Fair Value	28,358	24,144
U.S. Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,097	900
Fair Value	2,097	900
U.S. Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,085	10,040
Gross Unrealized Gains	5	9
Fair Value	$ 5,090	$ 10,049

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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