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Retirement Plans (Narrative) (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Jun. 30, 2019 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Retirement Plans [Line Items] |  |  |  |  |
Pension & OPEB Descriptions |  |  | Pension Plans – We provide defined benefit retirement income to eligible non-union employees through qualified and non-qualified (supplemental) pension plans. Qualified and non-qualified pension benefits are based on years of service and the highest compensation during the latest years of employment, with specific reductions made for early retirements. Non-union employees hired on or after January 1, 2018, are no longer eligible for pension benefits, but are eligible for an enhanced 401(k) benefit as described below in other retirement programs. Other Postretirement Benefits (OPEB) – We provide medical and life insurance benefits for eligible retirees hired before January 1, 2004. These benefits are funded as medical claims and life insurance premiums are paid. |  |
Changes in fair value period |  |  | 5 years |  |
OPEB Plan amendment (Note 5) | $ (92) |  |  | $ (92) |
Defined benefit plans | 69 |  | $ 231 | (42) | $ (62)
Deferred Tax Assets, Gross | $ 23 |  | $ 1,068 | $ 980 |
Future net periodic OPEB cost amortization duration | 8 years |  |  |  |
Discount rate - benefit obligations |  |  | 2.42% | 3.26% |
Pension Plan Master Trust future commitments for additonal contributions private equtiy partnerships |  |  | $ 147 | $ 189 |
Pension Plan Master Trust future commitments for additional contributions real estate partnerships and funds |  |  | 7 | 8 |
Pension [Member] |  |  |  |  |
Retirement Plans [Line Items] |  |  |  |  |
Accumulated benefit obligation |  |  | 560 | 498 |
Accumulated benefit obligation. |  |  | $ 5,200 | $ 4,500 |
Discount rate - benefit obligations |  |  | 2.42% | 3.26% |
Actual return (loss) on pension plan assets, net of fees |  |  | 16.00% | 20.00% | (2.00%)
OPEB [Member] |  |  |  |  |
Retirement Plans [Line Items] |  |  |  |  |
OPEB Plan amendment (Note 5) |  |  | $ (2) | $ (92) |
Discount rate - benefit obligations |  |  | 2.22% | 3.13% |
Health care cost trend rate (employees under 65) |  |  | 5.64% | 5.87% | 6.09%
Ultimate health care cost trend rate |  |  | 4.50% | 4.50% | 4.50%
Year ultimate trend rate reached |  |  | 2038 | 2038 | 2038
OPEB [Member] | Total 2021 Forecast [Member] |  |  |  |  |
Retirement Plans [Line Items] |  |  |  |  |
Health care cost trend rate (employees under 65) |  | 5.42% |  |  |
Ultimate health care cost trend rate |  | 4.50% |  |  |
Year ultimate trend rate reached |  | 2038 |  |  |

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- Definition The assumed health care cost trend rate used to measure the expected cost of benefits covered by the plan (gross eligible charges) for employees under age 65. This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + References No definition available. + Details
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- Definition The expected long-term rate of return on plan assets that is applied to a calculated value of plan assets that recognizes the changes in fair value over this period. + References No definition available. + Details
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- Definition The duration of time an amount is expected to be amortized into future defined benefit plan costs. + References No definition available. + Details
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- Definition Future Commitments for additional contributions to private equity partnerships by the Master Trust for a pension plan (defined beneift plan). + References No definition available. + Details
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