Benefit Plans - Change in Projected Benefit Obligation, Change in Fair Value of Plan Assets, and Funded Status of the Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	$ 190,849	$ 175,405
Interest cost	3,510	4,941	$ 6,113
Actuarial loss	(5,418)	18,813
Benefits paid	(8,737)	(8,310)
Projected benefit obligation at end of year	180,204	190,849	175,405
Change in fair value of plan assets:
Fair value of plan assets at beginning of year	260,651	236,621
Actual return on plan assets	25,057	30,987
Employer contributions	1,449	1,353
Benefits paid	(8,737)	(8,310)
Fair value of plan assets at end of year	278,420	260,651	$ 236,621
Funded status of the plan
Asset recognized	98,216	69,802
Accumulated benefit obligation	180,204	190,849
Accrued interest receivable	$ 783	$ 623