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Pension Plans and Postretirement Benefits - Components of Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | $ 7,900 | $ 11,800 | $ 12,400
Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | 7,515 | 11,116 | 11,667
Interest cost | 47,638 | 30,924 | 27,170
Expected return on plan assets | (60,437) | (83,254) | (81,778)
Amortization of prior service cost | 3,238 | 3,257 | 3,097
Recognized net actuarial loss (gain) | 31,755 | 52,202 | (34,690)
Net periodic benefit cost (income) | 29,709 | 14,245 | (74,534)
Other Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | 338 | 650 | 760
Interest cost | 2,139 | 1,387 | 1,197
Expected return on plan assets | (2,536) | (2,974) | (2,891)
Amortization of prior service cost | 40 | 26 | (178)
Recognized net actuarial loss (gain) | (946) | (5,616) | (4,876)
Net periodic benefit cost (income) | $ (965) | $ (6,527) | $ (5,988)

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- Definition Amount of prior service cost (credit) 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)(5) -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)(5) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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