Income Taxes - Reconciliation to Federal Statutory Income Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income taxes at U.S. federal statutory rate	$ 4,846	$ 3,945	$ 4,976
Provision-to-return adjustments	117	455	(66)
State income tax, net of federal tax effect	509	908	978
Tax credits	(1,274)	(958)	(2,196)
Contingent consideration	0	0	(1,050)
Stock-based compensation	(74)	255	151
Change in valuation allowance	(14)	(165)	173
Non-deductible compensation - 162(m)	510	0	0
Other	26	98	262
Total income tax provision	$ 4,646	$ 4,538	$ 3,228