Income Taxes - Reconciliation of Expected Statutory Federal Income Tax Provision to Actual Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Expected income tax benefit at federal statutory tax rate	$ (5,840)	$ (3,309)
State income taxes, net of federal benefit	1	(927)
Tax credits	(1,180)	(1,216)
Change in valuation allowance	6,659	2,606
Return to provision adjustments	80	(14)
Stock compensation	243	1,644
Reserve for uncertain tax positions	176	1,179
Other	(138)	37
Income tax expense	$ 1	$ 0