Retirement Benefits (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Pension Benefit Cost (Credit) | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | $ 1,486 | $ 1,686 | $ 4,619 | $ 5,598 |
| Interest cost | 7,640 | 8,104 | 22,935 | 24,400 |
| Expected return on plan assets | (10,336) | (10,273) | (31,155) | (30,786) |
| Amortization of prior service (credit) cost | (14) | 46 | (42) | 59 |
| Amortization of actuarial losses (gains) | 1,870 | 1,726 | 5,437 | 5,502 |
| Net periodic benefit (credit) | 646 | 1,289 | 1,794 | 4,773 |
| Other Postretirement Benefit Credit | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | 0 | 0 | 5 | 10 |
| Interest cost | 86 | 20 | 269 | 322 |
| Amortization of prior service (credit) cost | (20) | (16) | (53) | (45) |
| Amortization of actuarial losses (gains) | (222) | (414) | (536) | (586) |
| Net periodic benefit (credit) | $ (156) | $ (410) | $ (315) | $ (299) |
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- Definition Amount of gain (loss) 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 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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