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Benefit Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Actuarial (gain) loss | $ (84) | $ 205 |
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, accumulated benefit obligation | 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 | $ 160 |  |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 32.00% | 51.00% |
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 | $ 65 | $ 70 | $ 71
Pension Benefits |  |  |
Defined benefit plan, accumulated benefit obligation | 2,561 | 2,769 |
Actuarial (gain) loss | $ (84) | $ 205 |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 65.00% | 75.00% |
Limited partnership equity related hedge fund strategy plan assets | 76.00% |  |
Limited partnership hedge fund multi strategy plan assets | 19.00% |  |
Limited partnership hedge fund strategy distressed investments plan assets | 5.00% |  |
Defined benefit plan, expected future employer contributions, next fiscal year | $ 5 |  |
Postretirement Benefits |  |  |
Actuarial (gain) loss | $ 1 | $ 2 |
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 | 40.00% |  |
Maximum |  |  |
Defined benefit plan, plan assets, target allocation, percentage | 60.00% |  |

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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 http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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