Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Line Items]
Provision for income taxes	$ 0	$ 0	$ 0
Increase in valuation allowance	25,100,000	20,600,000
Total unrecognized tax benefit	8,401,000	7,272,000	$ 5,993,000	$ 4,964,000
Interest and penalties paid	$ 0
Earliest Tax Year [Member]
Income Taxes [Line Items]
Operating loss carryforwards expiration, beginning year	2030
Federal Income Tax
Income Taxes [Line Items]
Net operating loss	$ 389,700,000	332,500,000
Research and development tax credit	15,600,000	13,400,000
Federal Income Tax | Carryforwards Expiring 2030
Income Taxes [Line Items]
Net operating loss	$ 129,300,000
Federal Income Tax | Earliest Tax Year [Member]
Income Taxes [Line Items]
Operating loss carryforwards expiration, beginning year	2030
Federal Income Tax | Carryforwards Indefinitely
Income Taxes [Line Items]
Net operating loss	$ 260,400,000
State Income Tax
Income Taxes [Line Items]
Net operating loss	53,500,000	53,700,000
Research and development tax credit	$ 7,400,000	$ 6,300,000
State Income Tax | Earliest Tax Year [Member]
Income Taxes [Line Items]
Operating loss carryforwards expiration, beginning year	2030