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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 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 168,534 | $ 273,189
Gross Unrealized Holding Gains | 2 | 5
Gross Unrealized Holding Losses | (1,137) | (2,538)
Estimated Fair Value | 167,399 | 270,656
Corporate bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 41,760 | 83,080
Gross Unrealized Holding Gains | 1 | 0
Gross Unrealized Holding Losses | (457) | (1,072)
Estimated Fair Value | 41,304 | 82,008
Commercial paper [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 42,970 | 57,381
Gross Unrealized Holding Gains | 0 | 0
Gross Unrealized Holding Losses | 0 | 0
Estimated Fair Value | 42,970 | 57,381
U.S. government bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 72,130 | 112,547
Gross Unrealized Holding Gains | 1 | 5
Gross Unrealized Holding Losses | (565) | (1,207)
Estimated Fair Value | 71,566 | 111,345
Agency bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 9,183 | 11,690
Gross Unrealized Holding Gains | 0 | 0
Gross Unrealized Holding Losses | (108) | (222)
Estimated Fair Value | 9,075 | 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 | 2,491 | 2,484
Gross Unrealized Holding Gains | 0 | 0
Gross Unrealized Holding Losses | (7) | (10)
Estimated Fair Value | $ 2,484 | $ 2,474

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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