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Pension Benefits and Postretirement Benefits Other Than Pensions - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 USD ($) employees | Sep. 30, 2023 USD ($)
Pension Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Number of participants and beneficiaries | employees | 3,100 |
Percentage of compensation (as a percent) |  | 3.00%
Payments to participants of pension plan | $ 90.0 |
Contract purchase amount | 205.7 | $ 205.7
Noncash settlement charge | 70.2 |
Net assets of pension plan | 16.0 | $ 16.0
Noncash settlement charge, after tax | $ 55.5 |
Postretirement Benefits Other than Pensions |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Number of retired employees covered | employees | 300 |
Number of active employees covered | employees | 500 |

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- Definition Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans. + 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/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(10)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(7)(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(10)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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