Investments - Summary of Gross Unrealized Gains and Losses and Credit Losses (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 298,070	$ 423,153
Gross Unrealized Gains	101	397
Gross Unrealized Losses	(86)	(153)
Fair Value	298,085	423,397
U.S. Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,697	36,444
Gross Unrealized Gains		18
Gross Unrealized Losses	(1)	(5)
Fair Value	8,696	36,457
U.S. Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	197,070	268,841
Gross Unrealized Gains	68	305
Gross Unrealized Losses	(63)	(133)
Fair Value	197,075	269,013
International Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	53,106	52,411
Gross Unrealized Gains	32	65
Gross Unrealized Losses	(22)	(15)
Fair Value	53,116	52,461
U.S. Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	16,434	30,373
Fair Value	16,434	30,373
International Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	13,629	24,144
Fair Value	13,629	24,144
U.S. Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,040	900
Fair Value	3,040	900
U.S. Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	6,094	10,040
Gross Unrealized Gains	1	9
Fair Value	$ 6,095	$ 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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