Pension and Other Postretirement Plans (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Defined Benefit Plan Deferred Pension And Other Postretirement Benefit Plan Costs Recovered [Abstract] | ||||
| Deferred (recognized) pension and OPEB costs | $ (100) | $ (700) | ||
| Pension Benefits [Member] | ||||
| Components of net periodic benefit cost: | ||||
| Service cost | $ 583 | 655 | $ 1,202 | 1,306 |
| Interest cost | 4,062 | 4,313 | 8,073 | 8,569 |
| Expected return on assets | (7,790) | (7,246) | (15,526) | (14,507) |
| Amortization of: | ||||
| Actuarial (gain) loss | 59 | 102 | 103 | 150 |
| Net periodic benefit (credit) cost | (3,086) | (2,176) | (6,148) | (4,482) |
| Postretirement Benefits [Member] | ||||
| Components of net periodic benefit cost: | ||||
| Service cost | 177 | 188 | 352 | 371 |
| Interest cost | 677 | 754 | 1,359 | 1,514 |
| Expected return on assets | (712) | (634) | (1,419) | (1,358) |
| Amortization of: | ||||
| Transition obligation | 0 | 0 | 0 | 1 |
| Actuarial (gain) loss | (208) | (173) | (389) | (321) |
| Net periodic benefit (credit) cost | $ (66) | $ 135 | $ (97) | $ 207 |
| X | ||||||||||
- Definition Amount of net periodic benefit cost for pension and postretirement deferred (recognized prior year deferral) for the difference between estimated costs included in the rate settlement and actual costs incurred No definition available.
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- Definition Definedbenefitplandeferredpension And Other Postretirementbenefit Plan Costs Recovered Abstract No definition available.
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- References No definition available.
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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 transition asset (obligation) recognized in net periodic benefit (cost) credit of defined benefit plan. 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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- References No definition available.
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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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- Details
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- Details
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