Employee Benefit Plans - Components of net periodic benefit cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Pension settlement loss		$ 4,660
Retirement Income Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	0	$ 0
Interest cost	988	1,645	1,960
Expected return on plan assets	(1,509)	(1,581)	(2,598)
Amortization of net losses	808	986	919
Pension settlement loss		4,660
Net periodic benefit cost	$ 287	$ 5,710	$ 281