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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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