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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 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 121,874 | $ 273,189
Gross Unrealized Holding Gains | 30 | 5
Gross Unrealized Holding Losses | (6) | (2,538)
Estimated Fair Value | 121,898 | 270,656
Corporate bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 13,988 | 83,080
Gross Unrealized Holding Gains | 9 | 0
Gross Unrealized Holding Losses | (5) | (1,072)
Estimated Fair Value | 13,992 | 82,008
Commercial paper [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 52,273 | 57,381
Gross Unrealized Holding Gains | 0 | 0
Gross Unrealized Holding Losses | 0 | 0
Estimated Fair Value | 52,273 | 57,381
U.S. government bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 45,783 | 112,547
Gross Unrealized Holding Gains | 20 | 5
Gross Unrealized Holding Losses | 0 | (1,207)
Estimated Fair Value | 45,803 | 111,345
Agency bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 9,830 | 11,690
Gross Unrealized Holding Gains | 1 | 0
Gross Unrealized Holding Losses | (1) | (222)
Estimated Fair Value | $ 9,830 | 11,468
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
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

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