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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, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 273,189	$ 402,664
Gross Unrealized Holding Gains	5	2
Gross Unrealized Holding Losses	(2,538)	(903)
Estimated Fair Value	270,656	401,763
Corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	83,080	183,136
Gross Unrealized Holding Gains	0	2
Gross Unrealized Holding Losses	(1,072)	(492)
Estimated Fair Value	82,008	182,646
Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	57,381	68,079
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	0	0
Estimated Fair Value	57,381	68,079
U.S. government bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	112,547	91,840
Gross Unrealized Holding Gains	5	0
Gross Unrealized Holding Losses	(1,207)	(318)
Estimated Fair Value	111,345	91,522
Agency bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,690	23,339
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	(222)	(64)
Estimated Fair Value	11,468	23,275
Asset-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,484	27,105
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	(10)	(18)
Estimated Fair Value	2,474	27,087
Foreign government bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,007	9,165
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	(27)	(11)
Estimated Fair Value	4,980	$ 9,154
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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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).

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