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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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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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