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Retirement Plans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2024 | Sep. 30, 2024 | Sep. 30, 2023
Retirement Plans [Abstract] |  |  |  |  |
Service period of participants not impacted by pension plan amendment |  |  |  | 15 years |
Age of plan participants not impacted by pension plan amendment |  |  |  | 50 years |
Service period of participants who are age fifty not impacted by pension plan amendment |  |  |  | 10 years |
Higman [Member] |  |  |  |  |
Retirement Plans [Abstract] |  |  |  |  |
Pension contributions |  |  |  | $ 1,400 |
Higman [Member] | Scenario Forecast [Member] |  |  |  |  |
Retirement Plans [Abstract] |  |  |  |  |
Pension contributions |  |  | $ 300 |  |
Pension Plan [Member] |  |  |  |  |
Components of net periodic benefit cost [Abstract] |  |  |  |  |
Service cost | $ 850 | $ 924 |  | 2,547 | $ 2,772
Interest cost | 4,294 | 4,589 |  | 12,884 | 13,767
Expected return on plan assets | (6,221) | (5,727) |  | (18,663) | (17,182)
Amortization of actuarial (gain) loss | (584) | 0 |  | (1,748) | 0
Net periodic benefit cost | (1,661) | (214) |  | (4,980) | (643)
SERP [Member] |  |  |  |  |
Components of net periodic benefit cost [Abstract] |  |  |  |  |
Service cost | 0 | 0 |  | 0 | 0
Interest cost | 10 | 11 |  | 29 | 32
Expected return on plan assets | 0 | 0 |  | 0 | 0
Amortization of actuarial (gain) loss | 8 | 6 |  | 24 | 18
Net periodic benefit cost | 18 | 17 |  | 53 | 50
Other Postretirement Benefits Plan [Member] |  |  |  |  |
Components of net periodic benefit cost [Abstract] |  |  |  |  |
Interest cost | 5 | 6 |  | 15 | 17
Amortization of actuarial (gain) loss | (70) | (86) |  | (210) | (258)
Net periodic benefit cost | $ (65) | $ (80) |  | $ (195) | $ (241)

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- Definition The service period of eligible participants of the employee pension plan who have reached the age of fifty that will be grandfathered and not be impacted by the amendment to the pension plan. + References No definition available. + Details
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- Definition The service period of eligible participants of the employee pension plan who will be grandfathered and not be impacted by the amendment to the pension plan. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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