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Benefit Plans (Narrative) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2024 USD ($) extensionTerm | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Pension settlement transaction loss | $ 371 | $ 0 | $ 0
Pension settlement transaction gain (loss), net of tax | (293) |  |
Actuarial gain (loss) | 24 | (27) |
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, accumulated benefit obligation | 41 | 46 |
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, plan assets | $ 0 | $ 0 |
Assumptions used in calculating assumed health care cost trend rate | 4.00% |  |
Future capital call commitments for limited partnership investments | $ 90 |  |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 14.00% | 15.00% |
Defined contribution plan, maximum annual contributions per employee, percent | 50.00% |  |
Defined contribution plan, employer matching contribution, percent of match | 100.00% |  |
Defined contribution plan, employer matching contribution, percent of employees' gross pay | 6.00% |  |
Company contribution of eligible compensation, depending on age, percent | 5.00% |  |
Defined contribution plan, employers matching contribution, vesting period in years | 5 years |  |
Benefit expense for the Company's savings plan | $ 88 | $ 82 | $ 71
Pension Benefits |  |  |
Payment for pension settlement | 1,044 | 80 |
Pension settlement transaction loss (gain) | (1,044) | (86) |
Settlement through group annuity purchase |  | 80 |
Effect of pension settlement transactions |  | 86 |
Defined benefit plan, accumulated benefit obligation | 681 | 1,807 |
Actuarial gain (loss) | $ 24 | $ (27) |
Percentage of limited partnerships invested in private debt and equity | 99.00% | 94.00% |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 1.00% | 6.00% |
Defined benefit plan, expected future employer contributions, next fiscal year | $ 5 |  |
Pension Benefits | CANADA |  |  |
Pension settlement transaction loss | 4 |  |
Pension settlement transaction gain (loss), net of tax | (3) |  |
Pension Benefits | UNITED STATES |  |  |
Payment for pension settlement | 1,034 |  |
Pension settlement transaction loss (gain) | $ 1,045 |  |
Number of employees covered by settlement | extensionTerm | 7,600 |  |
Percentage of benefit obligation transferred | 60.00% |  |
Pension settlement transaction loss | $ 367 |  |
Pension settlement transaction gain (loss), net of tax | (290) |  |
Postretirement Benefits |  |  |
Payment for pension settlement | 0 | $ 0 |
Pension settlement transaction loss (gain) | 0 | 0 |
Actuarial gain (loss) | $ 0 | $ (4) |
Defined benefit plan, health care cost trend rate assumed for next fiscal year | 4.00% | 4.00% | 4.00%
Defined benefit plan, expected future employer contributions, next fiscal year | $ 1 |  |
Minimum |  |  |
Defined benefit plan, plan assets, target allocation, percentage | 0.00% |  |
Maximum |  |  |
Defined benefit plan, plan assets, target allocation, percentage | 40.00% |  |

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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (e) -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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- Definition Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets. + 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/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-3 + Details
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- Definition Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets. + 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/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-3 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + 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/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -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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- Definition Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -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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