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Benefit Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Actuarial (gain) loss | $ (514) | $ (84) |
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, accumulated benefit obligation | 49 | $ 61 |
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, plan assets | $ 0 |  |
Assumptions used in calculating assumed health care cost trend rate | 4.00% |  |
Future capital call commitments for limited partnership investments | $ 120 |  |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 24.00% | 32.00% |
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 | $ 71 | $ 65 | $ 70
Pension Benefits |  |  |
Defined benefit plan, accumulated benefit obligation | 1,931 | 2,561 |
Actuarial (gain) loss | $ (514) | $ (84) |
Percentage of limited partnerships invested in private debt and equity | 62.00% | 35.00% |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 38.00% | 65.00% |
Defined benefit plan, expected future employer contributions, next fiscal year | $ 6 |  |
Postretirement Benefits |  |  |
Actuarial (gain) loss | $ 0 | $ 1 |
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 -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920 + Details
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