Components of Net Periodic Benefit Cost - Net Periodic Benefit Cost (Details) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Pension plan | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | $ 104,000 | $ 107,000 | $ 208,000 | $ 215,000 |
| Interest cost | 990,000 | 1,017,000 | 1,980,000 | 2,033,000 |
| Expected return on plan assets | (1,216,000) | (1,093,000) | (2,432,000) | (2,187,000) |
| Net Periodic Benefit Cost | (122,000) | 31,000 | (244,000) | 61,000 |
| Postretirement Health Coverage | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | 6,000 | 3,000 | 11,000 | 6,000 |
| Interest cost | 38,000 | 32,000 | 75,000 | 64,000 |
| Net amortization of net (gain) loss | (30,000) | (39,000) | (60,000) | (78,000) |
| Net Periodic Benefit Cost | $ 14,000 | $ (4,000) | $ 26,000 | $ (8,000) |
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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 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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- Details
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- Details
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