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)