Employee Benefit Plans and Other Postretirement Benefits - Schedule Of Obligation And Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in plan assets:
Pension and postretirement assets	$ 386,152	$ 95,711
Pension and SERPA Benefits
Change in benefit obligation:
Benefit obligation, beginning of period	2,390,435	2,212,012
Service cost	24,570	27,224	$ 25,408
Interest cost	61,988	76,447	85,483
Actuarial (gains) losses	(92,157)	228,081
Plan participant contributions	0	0
Benefits paid	(138,043)	(137,381)
Net curtailments and settlements	(72,198)	(15,948)
Benefit obligation, end of period	2,174,595	2,390,435	2,212,012
Change in plan assets:
Fair value of plan assets, beginning of period	2,433,975	2,209,222
Return on plan assets	189,974	361,674
Plan participant contributions	0	0
Benefits paid	(137,482)	(136,921)
Fair value of plan assets, end of period	2,486,467	2,433,975	2,209,222
Funded status of the plan	311,872	43,540
Pension and postretirement assets	332,586	82,537
Accrued liabilities	(1,976)	(8,814)
Pension and Postretirement healthcare liabilities	(18,738)	(30,183)
Total benefits included in balance sheet	311,872	43,540
Prior service credits	2,457	(5,712)
Actuarial losses (gains)	232,622	445,804
Amounts included in other comprehensive income, net of tax	235,079	440,092
Postretirement Health Coverage
Change in benefit obligation:
Benefit obligation, beginning of period	315,245	293,505
Service cost	5,147	11,761	4,449
Interest cost	6,505	9,391	11,753
Actuarial (gains) losses	(24,190)	18,824
Plan participant contributions	2,337	2,140
Benefits paid	(18,743)	(19,703)
Net curtailments and settlements	0	(673)
Benefit obligation, end of period	286,301	315,245	293,505
Change in plan assets:
Fair value of plan assets, beginning of period	244,035	220,992
Return on plan assets	30,504	36,349
Plan participant contributions	2,337	2,140
Benefits paid	(13,931)	(15,446)
Fair value of plan assets, end of period	262,945	244,035	$ 220,992
Funded status of the plan	(23,356)	(71,210)
Pension and postretirement assets	53,566	13,174
Accrued liabilities	(361)	(361)
Pension and Postretirement healthcare liabilities	(76,561)	(84,023)
Total benefits included in balance sheet	(23,356)	(71,210)
Prior service credits	(3,661)	(5,438)
Actuarial losses (gains)	(36,905)	(4,942)
Amounts included in other comprehensive income, net of tax	$ (40,566)	$ (10,380)