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Balance Sheet Components - Summary of Contractual Maturities of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | $ 273,189 | $ 402,664
Estimated Fair Value | 270,656 | $ 401,763
Within one year - Bond and mutual funds |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 268,709 |
Estimated Fair Value | 266,308 |
After one year through three years |  |
Debt Securities, Available-for-Sale [Line Items] |  |
Amortized Cost | 4,480 |
Estimated Fair Value | $ 4,348 |

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