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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 | Mar. 31, 2026 | Dec. 31, 2025
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Amortized Cost | $ 1,010,863 | $ 1,191,065
Unrealized Gains | 352 | 1,296
Unrealized Losses | (1,018) | (124)
Fair Value | 1,010,197 | 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 | 65,528 | 89,509
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Fair Value | 65,528 | 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 | 203,112 | 239,097
Unrealized Gains | 196 | 574
Unrealized Losses | (31) | (7)
Fair Value | 203,277 | 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 | 208,017 | 201,788
Unrealized Gains | 29 | 162
Unrealized Losses | (316) | (38)
Fair Value | 207,730 | 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 | 203,988 | 289,447
Unrealized Gains | 6 | 96
Unrealized Losses | (130) | (26)
Fair Value | 203,864 | 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 | 7,633 | 7,579
Unrealized Gains | 0 | 7
Unrealized Losses | (2) | 0
Fair Value | 7,631 | 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 | 322,585 | 363,645
Unrealized Gains | 121 | 457
Unrealized Losses | (539) | (53)
Fair Value | $ 322,167 | $ 364,049

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