Pension Plans and Postretirement Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
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| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | $ 3,300 | $ 1,900 | $ 5,000 | $ 4,000 |
| Pension Benefits | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | 2,897 | 1,768 | 4,580 | 3,765 |
| Interest cost | 13,782 | 11,133 | 25,235 | 22,763 |
| Expected return on plan assets | (16,987) | (14,654) | (30,991) | (30,153) |
| Amortization of prior service cost | 792 | 820 | 1,583 | 1,640 |
| Net periodic benefit (income) / loss | 484 | (933) | 407 | (1,985) |
| Other Benefits | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | 384 | 96 | 469 | 193 |
| Interest cost | 869 | 503 | 1,401 | 1,008 |
| Expected return on plan assets | (487) | (487) | (973) | (974) |
| Amortization of prior service cost | 22 | 12 | 44 | 23 |
| Net periodic benefit (income) / loss | $ 788 | $ 124 | $ 941 | $ 250 |
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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