Postretirement Benefits - Fair Value Measurement for Pension Plan Assets by Major Category and Level of Input (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fair value measurements of pension plan assets:
Total	$ 829,866	$ 1,140,243	$ 1,081,061
Employee pension plan | Qualified Plan | Funded Plan
Fair value measurements of pension plan assets:
Total	829,866	1,140,243
Employee pension plan | Qualified Plan | Funded Plan | Level 1 Fair Value
Fair value measurements of pension plan assets:
Total	327,080	153,205
Employee pension plan | Qualified Plan | Funded Plan | Level 2 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Level 3 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Net Asset Value (NAV)
Fair value measurements of pension plan assets:
Total	502,786	987,038
Employee pension plan | Qualified Plan | Funded Plan | Total equity securities
Fair value measurements of pension plan assets:
Total	379,419	506,389
Employee pension plan | Qualified Plan | Funded Plan | Total equity securities | Level 1 Fair Value
Fair value measurements of pension plan assets:
Total	315,637	139,688
Employee pension plan | Qualified Plan | Funded Plan | Total equity securities | Level 2 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Total equity securities | Level 3 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Total equity securities | Net Asset Value (NAV)
Fair value measurements of pension plan assets:
Total	63,782	366,701
Employee pension plan | Qualified Plan | Funded Plan | U.S. equity securities
Fair value measurements of pension plan assets:
Total	219,410	305,440
Employee pension plan | Qualified Plan | Funded Plan | U.S. equity securities | Level 1 Fair Value
Fair value measurements of pension plan assets:
Total	204,838	0
Employee pension plan | Qualified Plan | Funded Plan | U.S. equity securities | Level 2 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | U.S. equity securities | Level 3 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | U.S. equity securities | Net Asset Value (NAV)
Fair value measurements of pension plan assets:
Total	14,572	305,440
Employee pension plan | Qualified Plan | Funded Plan | Non-U.S. equity securities
Fair value measurements of pension plan assets:
Total	160,009	200,949
Employee pension plan | Qualified Plan | Funded Plan | Non-U.S. equity securities | Level 1 Fair Value
Fair value measurements of pension plan assets:
Total	110,799	139,688
Employee pension plan | Qualified Plan | Funded Plan | Non-U.S. equity securities | Level 2 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Non-U.S. equity securities | Level 3 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Non-U.S. equity securities | Net Asset Value (NAV)
Fair value measurements of pension plan assets:
Total	49,210	61,261
Employee pension plan | Qualified Plan | Funded Plan | Debt securities
Fair value measurements of pension plan assets:
Total	439,004	620,337
Employee pension plan | Qualified Plan | Funded Plan | Debt securities | Level 1 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Debt securities | Level 2 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Debt securities | Level 3 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Debt securities | Net Asset Value (NAV)
Fair value measurements of pension plan assets:
Total	439,004	620,337
Employee pension plan | Qualified Plan | Funded Plan | Other
Fair value measurements of pension plan assets:
Total	11,443	13,517
Employee pension plan | Qualified Plan | Funded Plan | Other | Level 1 Fair Value
Fair value measurements of pension plan assets:
Total	11,443	13,517
Employee pension plan | Qualified Plan | Funded Plan | Other | Level 2 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Other | Level 3 Fair Value
Fair value measurements of pension plan assets:
Total	0	0
Employee pension plan | Qualified Plan | Funded Plan | Other | Net Asset Value (NAV)
Fair value measurements of pension plan assets:
Total	$ 0	$ 0