v3.25.4

Retirement Benefits (Summary of Changes in the Fair Value of the Plans Level 3 Assets) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | $ 12,575 |
Fair value of plan assets at end of year | 13,072 | $ 12,575
Corporate stocks |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 375 |
Fair value of plan assets at end of year | 140 | 375
Insurance group annuity contracts |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 164 |
Fair value of plan assets at end of year | 2,722 | 164
Other investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 271 |
Fair value of plan assets at end of year | 342 | 271
Net derivative liabilities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | (573) |
Fair value of plan assets at end of year | (193) | (573)
Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 290 | 303
Purchases | 2,482 | 17
Sales | 58 | (18)
Settlements | (75) | (13)
Unrealized Gain/ (Loss) | 12 | 6
Realized Gain/ (Loss) | 0 | 0
Exchange Rate Impact | 94 | (5)
Transfers in/(out) and Other | 0 | 0
Fair value of plan assets at end of year | 2,861 | 290
Significant Unobservable Inputs (Level 3) | Total investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 414 | 437
Purchases | 2,482 | 17
Sales | (20) | (18)
Settlements | (75) | (13)
Unrealized Gain/ (Loss) | 72 | (2)
Realized Gain/ (Loss) | 0 | 0
Exchange Rate Impact | 103 | (7)
Transfers in/(out) and Other | 0 | 0
Fair value of plan assets at end of year | 2,976 | 414
Significant Unobservable Inputs (Level 3) | Corporate stocks |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1 | 1
Fair value of plan assets at end of year | 1 | 1
Significant Unobservable Inputs (Level 3) | Insurance group annuity contracts |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 164 | 185
Purchases | 2,468 |
Settlements | (75) | (13)
Unrealized Gain/ (Loss) | 92 | (18)
Exchange Rate Impact | 73 | 10
Fair value of plan assets at end of year | 2,722 | 164
Significant Unobservable Inputs (Level 3) | Other investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 249 | 251
Purchases | 14 | 17
Sales | (20) | (18)
Unrealized Gain/ (Loss) | (20) | 16
Realized Gain/ (Loss) | 0 | 0
Exchange Rate Impact | 30 | (17)
Transfers in/(out) and Other | 0 | 0
Fair value of plan assets at end of year | 253 | 249
Significant Unobservable Inputs (Level 3) | Net derivative liabilities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | (124) | (134)
Sales | 78 |
Unrealized Gain/ (Loss) | (60) | 8
Exchange Rate Impact | (9) | 2
Fair value of plan assets at end of year | $ (115) | $ (124)

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