v3.20.4

Pension And Postretirement Benefits (Narrative) (Details) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Combined net pension and postretirement cost |  |  |  | $ 711,000,000 | $ 2,762,000,000 | $ (4,251,000,000)
Increase (decrease) in plan benefit obligations due to change in assumed rates |  |  |  | $ (2,992,000,000) | $ (2,002,000,000) | (1,148,000,000)
Composite rate of compensation increase for determining benefit obligation | 3.00% | 3.00% |  | 3.00% | 3.00% |
Discretionary contributions to postretirement plan | $ 425,000,000 | $ 200,000,000 |  |  |  |
Debt-financed shares held by ESOPs (allocated or unallocated) | 0 |  |  | $ 0 |  |
Benefit cost of the contributory savings plans |  |  |  | 814,000,000 | $ 793,000,000 | 724,000,000
Forecast |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Increase (decrease) in plan benefit obligations due to change in assumed rates |  |  | $ 277,000,000 |  |  |
Assumptions used, percentage change in weighted-average interest crediting rate that would impact pension benefit obligation |  |  | (0.50%) |  |  |
Pension Benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Special termination benefits |  |  |  | 0 | 81,000,000 |
Accumulated benefit obligation for pension plans | $ 60,848,000,000 | $ 58,150,000,000 |  | 60,848,000,000 | 58,150,000,000 |
Combined net pension and postretirement cost |  |  |  | $ 1,450,000,000 | $ 2,393,000,000 | $ (909,000,000)
Discount rate for determining projected benefit obligation | 2.70% | 3.40% |  | 2.70% | 3.40% | 4.50%
Decrease in discount rate over prior year |  |  |  | 0.70% | 1.10% |
Increase (decrease) in plan benefit obligations due to change in assumed rates |  |  |  | $ 5,594,000,000 | $ 8,018,000,000 |
Long-term rate of return on plan assets |  |  |  | 7.00% | 7.00% | 7.00%
Composite rate of compensation increase for determining benefit obligation | 3.00% | 3.00% |  | 3.00% | 3.00% | 3.00%
Preferred equity interest value | $ 54,606,000,000 | $ 53,530,000,000 |  | $ 54,606,000,000 | $ 53,530,000,000 | $ 51,681,000,000
Aggregate percentage of the fair value of investments to the fair value of total plan assets held as of the measurement date | 11.00% |  |  | 11.00% |  |
Pension Benefits | Level 3 |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Preferred equity interest value | $ 8,390,000,000 | 11,639,000,000 |  | $ 8,390,000,000 | 11,639,000,000 | 11,333,000,000
Pension Benefits | Preferred interest |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Preferred equity interest value | 5,771,000,000 | 8,806,000,000 |  | 5,771,000,000 | 8,806,000,000 |
Pension Benefits | Preferred interest | Level 3 |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Preferred equity interest value | $ 5,771,000,000 | 8,806,000,000 |  | 5,771,000,000 | 8,806,000,000 |
Pension Benefits | Mobility II, LLC | Preferred interest |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Preferred equity interest value held by pension trust |  | $ 8,806,000,000 |  |  | 8,806,000,000 |
Value of portion of preferred interest sold to third party investors |  |  |  | 2,885,000,000 |  |
Pension Benefits | Forecast |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Long-term rate of return on plan assets |  |  | 6.75% |  |  |
Downward adjustment to expected long-term rate of return on plan assets |  |  | 0.25% |  |  |
Postretirement Benefits |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Special termination benefits |  |  |  | 0 | 0 |
Combined net pension and postretirement cost |  |  |  | $ (739,000,000) | $ 369,000,000 | $ (3,342,000,000)
Discount rate for determining projected benefit obligation | 2.40% | 3.20% |  | 2.40% | 3.20% | 4.40%
Decrease in discount rate over prior year |  |  |  | 0.80% | 1.20% |
Increase (decrease) in plan benefit obligations due to change in assumed rates |  |  |  | $ 1,311,000,000 | $ 2,399,000,000 |
Long-term rate of return on plan assets |  |  |  | 4.75% | 5.75% | 5.75%
Composite rate of compensation increase for determining benefit obligation | 3.00% | 3.00% |  | 3.00% | 3.00% | 3.00%
Preferred equity interest value | $ 3,843,000,000 | $ 4,145,000,000 |  | $ 3,843,000,000 | $ 4,145,000,000 | $ 4,277,000,000
Aggregate percentage of the fair value of investments to the fair value of total plan assets held as of the measurement date | 1.00% |  |  | 1.00% |  |
Postretirement Benefits | Level 3 |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Preferred equity interest value | $ 4,000,000 | $ 32,000,000 |  | $ 4,000,000 | 32,000,000 | 13,000,000
Postretirement Benefits | Forecast |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Long-term rate of return on plan assets |  |  | 4.50% |  |  |
Downward adjustment to expected long-term rate of return on plan assets |  |  | 0.25% |  |  |
Healthcare Benefits | Prescription Drug Cost - Eligible Participants |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Increase (decrease) in plan benefit obligations due to change in assumed rates |  |  |  |  | $ (102,000,000) |
Assumed annual and ultimate health care cost trend rate for next fiscal year | 4.00% |  |  | 4.00% |  |
Estimated annual growth rate for health care cost | 4.00% | 4.50% |  | 4.00% | 4.50% |
Healthcare Benefits | Medical Cost - Eligible Participants |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Increase (decrease) in plan benefit obligations due to change in assumed rates |  |  |  |  | $ (102,000,000) |
Assumed annual and ultimate health care cost trend rate for next fiscal year | 4.00% |  |  | 4.00% |  |
Estimated annual growth rate for health care cost | 4.00% | 4.50% |  | 4.00% | 4.50% |
Healthcare Benefits | Administrative Expense |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Percent of growth assumed |  |  |  | 2.50% |  |
Healthcare Benefits | Administrative Expense | Forecast |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Percent of growth assumed |  |  | 2.50% |  |  |
Healthcare Benefits | Dental Claims |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Percent of growth assumed |  |  |  | 3.00% |  |
Healthcare Benefits | Dental Claims | Forecast |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Percent of growth assumed |  |  | 3.00% |  |  |
Supplemental Employee Retirement Plan |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Combined net pension and postretirement cost |  |  |  | $ 330,000,000 | $ 438,000,000 |
Discount rate for determining projected benefit obligation | 2.30% | 3.20% |  | 2.30% | 3.20% |
Projected benefit obligation | $ 2,687,000,000 | $ 2,605,000,000 |  | $ 2,687,000,000 | $ 2,605,000,000 |
Deferred compensation expense |  |  |  | $ 183,000,000 | $ 199,000,000 | $ 128,000,000

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