Fair Value Measurements - Summary of Fair Value of Financial Assets Consists of Cash Equivalents and Investments Classified as Available-for-sale Securities Measured on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - Cash and Cash Equivalents and Investments [Member] - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	$ 1,641,903	$ 1,191,065
Unrealized Gains	121	1,296
Unrealized Losses	(2,557)	(124)
Fair Value	1,639,467	1,192,237
Money Market Funds [Member] \| Fair Value Measurements Using Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	150,838	89,509
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	150,838	89,509
U.S. Treasury Securities [Member] \| Fair Value Measurements Using Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	356,077	239,097
Unrealized Gains	47	574
Unrealized Losses	(436)	(7)
Fair Value	355,688	239,664
U.S. Government agency securities \| Fair Value Measurements Using Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	270,636	201,788
Unrealized Gains	0	162
Unrealized Losses	(813)	(38)
Fair Value	269,823	201,912
Commercial Paper [Member] \| Fair Value Measurements Using Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	435,841	289,447
Unrealized Gains	6	96
Unrealized Losses	(475)	(26)
Fair Value	435,372	289,517
Asset-backed securities [Member] \| Fair Value Measurements Using Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	7,687	7,579
Unrealized Gains	0	7
Unrealized Losses	(3)	0
Fair Value	7,684	7,586
Corporate Obligations [Member] \| Fair Value Measurements Using Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortized Cost	420,824	363,645
Unrealized Gains	68	457
Unrealized Losses	(830)	(53)
Fair Value	$ 420,062	$ 364,049

Fair Value Measurements - Summary of Fair Value of Financial Assets Consists of Cash Equivalents and Investments Classified as Available-for-sale Securities Measured on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - Cash and Cash Equivalents and Investments [Member] - USD ($)
$ in Thousands

Jun. 30, 2026

Dec. 31, 2025

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]

Amortized Cost

$ 1,641,903

$ 1,191,065

Unrealized Gains

121

1,296

Unrealized Losses

(2,557)

(124)