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Employee Postretirement Benefits - Narrative (Details) - Pension Plan - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Oct. 31, 2023 | Sep. 30, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Oct. 01, 2023 | Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Contributions by employer |  |  | $ 0 | $ 20,000,000 |  |
Reduction from plan amendment |  |  | $ (20,100,000) |  |  |
Reduction attributable to increase in discount rate to measurement plan liability |  | $ 2,600,000 |  |  |  |
Discount rate (as a percent) |  | 6.06% | 6.06% |  |  | 5.52%
Subsequent Event |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Savings attributable to the plan change | $ 17,500,000 |  |  |  |  |
Expected remaining service period (in years) |  |  |  |  | 4 years 9 months 18 days |

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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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