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Postretirement Benefit Obligations - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Retirement Benefits [Abstract] |  |  |
Service cost | $ 4,877 | $ 4,906 | $ 6,860
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent
Interest cost | $ 4,524 | $ 4,048 | $ 2,436
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent
Expected return on plan assets | $ (4,884) | $ (4,396) | $ (4,463)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Immediate Recognition of Actuarial Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent
Recognition of actuarial losses | $ 0 | $ 0 | $ 0
Net periodic Pension Cost | 4,517 | 4,558 | 4,833
Other changes in benefits obligations recognized in other comprehensive loss (income) |  |  |
Actuarial losses (gains) | (13,455) | (184) | (2,157)
Total recognized in other comprehensive income | (13,455) | (184) | (2,157)
Total net periodic pension cost (benefit) recognized in Other comprehensive income | $ (8,938) | $ 4,374 | $ 2,676

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- Definition Amount of gain (loss), recognized immediately as component of net periodic benefit (cost) credit, for change in value of benefit obligation or plan assets from experience different from that assumed, change in actuarial assumption, or consequence of temporarily deviating from substantive plan. Includes, but is not limited to, amount in excess of 10 percent of greater of fair value of plan assets or benefit obligation. + References Reference 1: 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 2: 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 3: 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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- 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. + 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)(3) -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)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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