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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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