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Pension Plans and Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Nov. 30, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost |  | $ 7,900 | $ 11,800 | $ 12,400
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Other – net | Other – net | Other – net
Net periodic defined benefits expense (reversal), excluding service cost |  | $ (20,900) | $ 4,000 | $ 92,900
Other comprehensive (income) loss, net periodic benefit cost |  | 3,200 |  |
Other comprehensive (income) loss, pension benefits and other benefits |  | $ 0 |  |
Percentage of investment return on domestic plan assets |  | 7.00% | (22.00%) |
Vesting period for employer matching contributions |  | 3 years |  |
Thrift Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of matching contribution by employer |  | 50.00% |  |
Thrift Plan | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer matching percentage |  | 6.00% |  |
Thrift Plan and MII Thrift Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer contributions |  | $ 41,500 | $ 37,600 | 37,500
Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost |  | 7,515 | 11,116 | $ 11,667
Increase in pension plan benefit obligation |  | 33,200 | (295,100) |
Pension settlement-related charges | $ 12,600 |  |  |
Pension, benefit obligation, payment for settlement | $ 48,800 |  |  |
Pension settlement related charges |  | $ 0 | $ 48,777 |

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- Definition Defined benefit plan amounts recognized in net periodic pension cost and other comprehensive income. + References No definition available. + Details
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- Definition Defined benefit plan, percentage of investment return on plan assets. + References No definition available. + Details
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- Definition Defined Contribution Plan, Vesting Period For Employer Matching Contributions + References No definition available. + Details
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- Definition Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(10) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -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)(7) -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)(7) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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