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Fair Value Measurements - Summary of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 304,916	$ 422,581
Unrealized Gains	257
Unrealized Losses	(40)	(806)
Fair Value	305,133	421,775
Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	160,657	321,630
Unrealized Gains	149
Unrealized Losses		(205)
Fair Value	160,806	321,425
Federal Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	28,998	36,192
Unrealized Losses	(40)	(35)
Fair Value	28,958	36,157
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	47,150
Unrealized Gains	62
Fair Value	47,212
U.S. Treasury [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	68,111	64,759
Unrealized Gains	46
Unrealized Losses		(566)
Fair Value	$ 68,157	$ 64,193

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