v3.25.4

Retirement Benefits (Schedule of Allocation of Plan Assets) (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | --- | ---
DB Pension Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | $ 3,177 | $ 2,964 | $ 3,004
DB Pension Plans | Plan Assets Excluding Pooled Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 162 | 148 |
DB Pension Plans | Plan Assets Excluding Pooled Funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 162 | 148 |
DB Pension Plans | Plan Assets Excluding Pooled Funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
DB Pension Plans | Cash and short-term investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 162 | 148 |
DB Pension Plans | Cash and short-term investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 162 | 148 |
DB Pension Plans | Cash and short-term investments | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
DB Pension Plans | Mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
DB Pension Plans | Mutual funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
DB Pension Plans | Mutual funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
DB Pension Plans | Pooled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 3,015 | 2,816 |
OPEB Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 1,733 | 1,588 | $ 1,559
OPEB Plan | Plan Assets Excluding Pooled Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 466 | 356 |
OPEB Plan | Plan Assets Excluding Pooled Funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 362 | 258 |
OPEB Plan | Plan Assets Excluding Pooled Funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 104 | 98 |
OPEB Plan | Cash and short-term investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 72 | 35 |
OPEB Plan | Cash and short-term investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 72 | 35 |
OPEB Plan | Cash and short-term investments | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
OPEB Plan | U.S. government and agencies securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 15 | 13 |
OPEB Plan | U.S. government and agencies securities | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
OPEB Plan | U.S. government and agencies securities | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 15 | 13 |
OPEB Plan | Corporate debt |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 69 | 68 |
OPEB Plan | Corporate debt | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
OPEB Plan | Corporate debt | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 69 | 68 |
OPEB Plan | State and municipal bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 4 | 2 |
OPEB Plan | State and municipal bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
OPEB Plan | State and municipal bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 4 | 2 |
OPEB Plan | Foreign bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 16 | 15 |
OPEB Plan | Foreign bonds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
OPEB Plan | Foreign bonds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 16 | 15 |
OPEB Plan | Common stocks |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 215 | 170 |
OPEB Plan | Common stocks | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 215 | 170 |
OPEB Plan | Common stocks | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
OPEB Plan | Mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 75 | 53 |
OPEB Plan | Mutual funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 75 | 53 |
OPEB Plan | Mutual funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | 0 | 0 |
OPEB Plan | Pooled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets | $ 1,267 | $ 1,232 |

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