Income Tax - Summary Of Major Components Of Deferred Tax Assets And Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets
Net operating loss carryforwards	$ 90,562	$ 28,878
Research and development tax credits	31,908	15,961
Accruals and reserves	14,392	23,804
Lease liability	14,192	0
Intangibles	43,261	1,339
Stock-based compensation	6,601	1,427
Total deferred tax assets	200,916	71,409
Valuation allowance	(186,853)	(66,456)
Net deferred tax assets	14,063	4,953
Deferred tax liabilities
Fixed assets	(3,750)	(4,946)
Right-of-use assets	(10,388)	0
Total deferred tax liabilities	(14,138)	(4,946)
Net deferred taxes	$ (75)
Net deferred taxes		$ 7