Income Taxes - Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 57,073	$ 36,922
Research and development credits	7,367	6,246
Other intangibles	5	5
Accruals and reserves	686	583
Stock-based compensation	3,041	995
Tenant improvement allowances		257
Lease liabilities	7,340
Unrealized gain/loss on investments	240
Total gross deferred tax assets	75,752	45,008
Less: valuation allowance	(69,147)	(44,745)
Total deferred tax assets, net	6,605	263
Fixed assets	(2,290)	(263)
Right-of-use assets	(4,315)
Total gross deferred tax liabilities	$ (6,605)	$ (263)