Income Taxes - Reconciliation of U.S. Federal Statutory Income Tax Rate to Company's Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	(21.00%)	(21.00%)
State taxes, net of federal benefit	(6.90%)	(5.70%)
Federal and state research and development tax credits	(2.40%)	(3.60%)
Nondeductible items	(3.20%)	(0.20%)
Deferred tax effect of change in state blended rate	(1.70%)	7.80%
Return to provision	1.10%	1.70%
Other	(0.20%)	(0.00%)
Change in deferred tax asset valuation allowance	34.30%	20.90%
Effective income tax rate	(0.00%)	(0.10%)