Employee Benefit Plans - Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Summary of employee benefits charged to operating expenses
Payroll taxes	$ 441	$ 435
Medical plans	475	450
401(k) match and profit sharing	369	499
Periodic pension cost	437	416
Other	8	4
Total employee benefits	$ 1,730	$ 1,804