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Share-based Compensation and Employee Benefits - Pensions and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Savings plan - defined contribution plan |  |  |
Pension and Other Postretirement Benefit Plans |  |  |
Percentage of eligible compensation contributed | 5.00% |  |
Plan vesting period | 2 years |  |
Plan cost | $ 56 | $ 53 | $ 51
Pension Benefits |  |  |
Pension and Other Postretirement Benefit Plans |  |  |
Percentage of employees covered | 100.00% |  |
Vesting period | 3 years |  |
Settlements |  | $ 179 |
OPEB |  |  |
Pension and Other Postretirement Benefit Plans |  |  |
Medicare participation, age | 65 |  |
Actuarial Assumptions and Sensitivity Analysis |  |  |
Weighted-average annual rate of increase in the per capita cost of covered health care benefits | 8.03% |  |
Ultimate health care cost trend rate | 4.00% |  |

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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 Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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