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Balance Sheet Components - Summary of Amortized Cost, Gross Unrealized Holding Gains or Losses, and Fair Value of Available-for-Sale Investments (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 130,545 | $ 273,189
Gross Unrealized Holding Gains | 5 | 5
Gross Unrealized Holding Losses | (124) | (2,538)
Estimated Fair Value | 130,426 | 270,656
Corporate bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 11,987 | 83,080
Gross Unrealized Holding Gains | 0 | 0
Gross Unrealized Holding Losses | (77) | (1,072)
Estimated Fair Value | 11,910 | 82,008
Commercial paper [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 55,859 | 57,381
Gross Unrealized Holding Gains | 0 | 0
Gross Unrealized Holding Losses | (1) | 0
Estimated Fair Value | 55,858 | 57,381
U.S. government bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 57,734 | 112,547
Gross Unrealized Holding Gains | 3 | 5
Gross Unrealized Holding Losses | (46) | (1,207)
Estimated Fair Value | 57,691 | 111,345
Agency bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 4,965 | 11,690
Gross Unrealized Holding Gains | 2 | 0
Gross Unrealized Holding Losses | 0 | (222)
Estimated Fair Value | $ 4,967 | 11,468
Foreign government bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost |  | 5,007
Gross Unrealized Holding Gains |  | 0
Gross Unrealized Holding Losses |  | (27)
Estimated Fair Value |  | 4,980
Convertible promissory note [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost |  | 1,000
Gross Unrealized Holding Gains |  | 0
Gross Unrealized Holding Losses |  | 0
Estimated Fair Value |  | 1,000
Asset-backed securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost |  | 2,484
Gross Unrealized Holding Gains |  | 0
Gross Unrealized Holding Losses |  | (10)
Estimated Fair Value |  | $ 2,474

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