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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, 2021 | Dec. 31, 2020
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 402,664 | $ 8,272
Gross Unrealized Holding Gains | 2 | 119
Gross Unrealized Holding Losses | (903) | (3)
Fair Value | 401,763 | 8,388
Corporate bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 183,136 |
Gross Unrealized Holding Gains | 2 |
Gross Unrealized Holding Losses | (492) |
Fair Value | 182,646 |
Commercial paper [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 68,079 |
Gross Unrealized Holding Gains | 0 |
Gross Unrealized Holding Losses | 0 |
Fair Value | 68,079 |
U.S. government bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 91,840 |
Gross Unrealized Holding Gains | 0 |
Gross Unrealized Holding Losses | (318) |
Fair Value | 91,522 |
Agency bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 23,339 |
Gross Unrealized Holding Gains | 0 |
Gross Unrealized Holding Losses | (64) |
Fair Value | 23,275 |
Asset-backed securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 27,105 |
Gross Unrealized Holding Gains | 0 |
Gross Unrealized Holding Losses | (18) |
Fair Value | 27,087 |
Foreign government bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 9,165 |
Gross Unrealized Holding Gains | 0 |
Gross Unrealized Holding Losses | (11) |
Fair Value | $ 9,154 |
Bond and mutual funds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost |  | 8,147
Gross Unrealized Holding Gains |  | 0
Gross Unrealized Holding Losses |  | (3)
Fair Value |  | 8,144
Equity investments [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost |  | 125
Gross Unrealized Holding Gains |  | 119
Gross Unrealized Holding Losses |  | 0
Fair Value |  | $ 244

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