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Pensions and Other Postretirement Benefits - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 5 Months Ended
--- | --- | ---
Jun. 30, 2024 | May 31, 2024
Pension Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Curtailment gain |  | $ 0
Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Curtailment gain | $ 20 |
Percent reduction in future years of service of plan participants (as a percent) |  | 10.00%

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees. + 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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