Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 2,582	$ 669
Decrease in gross balance of property and equipment	(1,800)
Decrease in accumulated depreciation	$ (1,800)
Computer Hardware and Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Multi-tenant Building under Operating Lease [Member]
Property, Plant and Equipment [Line Items]
Decrease in gross balance of property and equipment	$ (3,300)
Decrease in accumulated depreciation	(1,200)
Depreciated gross balance of property and equipment	$ 2,100