Retirement Plans and Other Postretirement Benefits - Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 847,311	$ 783,203
U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	664,630	617,436
Municipal bonds \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1,456
Corporate debt instruments \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	2,595
Corporate debt instruments – Preferred \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	18,027
Corporate stocks – Common \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	56,955	56,258
Registered investment companies \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	92,336	145,380
U.S. Government securities \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1,141
Total investments \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	149,291	224,857
Investments measured at net asset value \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	515,339	392,579
Level 1 \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	149,291	201,638
Level 1 \| Municipal bonds \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 1 \| Corporate debt instruments \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 1 \| Corporate debt instruments – Preferred \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 1 \| Corporate stocks – Common \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	56,955	56,258
Level 1 \| Registered investment companies \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	92,336	145,380
Level 1 \| U.S. Government securities \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 1 \| Total investments \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	149,291	201,638
Level 1 \| Investments measured at net asset value \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 2 \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	23,219
Level 2 \| Municipal bonds \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1,456
Level 2 \| Corporate debt instruments \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	2,595
Level 2 \| Corporate debt instruments – Preferred \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	18,027
Level 2 \| Corporate stocks – Common \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 2 \| Registered investment companies \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 2 \| U.S. Government securities \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1,141
Level 2 \| Total investments \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	23,219
Level 2 \| Investments measured at net asset value \| U.S. Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

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