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Fair Value Measurements - Summary of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 285,166	$ 422,581
Unrealized Losses	(455)	(806)
Fair Value	284,711	421,775
Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	179,096	321,630
Unrealized Losses	(112)	(205)
Fair Value	178,984	321,425
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	7,899
Unrealized Losses	(22)
Fair Value	7,877
Federal Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	49,927	36,192
Unrealized Losses	(190)	(35)
Fair Value	49,737	36,157
U.S. Treasury [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	48,244	64,759
Unrealized Losses	(131)	(566)
Fair Value	$ 48,113	$ 64,193

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- Definition

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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