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Fair Value Measurements - Summary of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 428,043	$ 304,916
Unrealized Gains		257
Unrealized Losses	(756)	(40)
Fair Value	427,287	305,133
Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	180,927	160,657
Unrealized Gains		149
Unrealized Losses	(101)
Fair Value	180,826	160,806
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	47,604	47,150
Unrealized Gains		62
Unrealized Losses	(72)
Fair Value	47,532	47,212
U.S. Treasury [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	176,012	68,111
Unrealized Gains		46
Unrealized Losses	(548)
Fair Value	175,464	68,157
Federal Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	23,500	28,998
Unrealized Losses	(35)	(40)
Fair Value	$ 23,465	$ 28,958

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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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