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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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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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