Benefit Plans - Change in Plan Assets (Details) - Pension Plans - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance - plan assets at fair value	$ 319,699	$ 276,699
Actual return on plan assets	16,427	40,680
Employer contributions	6,800	16,250
Benefits and expenses paid	(14,676)	(13,930)
Ending balance - plan assets at fair value	$ 328,250	$ 319,699