Annual report [Section 13 and 15(d), not S-K Item 405]

PENSION AND OTHER POSTRETIREMENT BENEFITS - Obligations and Funded Status (Details)

v3.25.4
PENSION AND OTHER POSTRETIREMENT BENEFITS - Obligations and Funded Status (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Amounts recognized in Statements of Financial Position:          
Pension and OPEB assets $ 469 $ 427 $ 469 $ 427  
Non-current liabilities (655) (751) (655) (751)  
Amounts recognized in accumulated other comprehensive loss (income):          
Accumulated benefit obligation 4,120 4,236 4,120 4,236  
Pension Benefits          
Change in benefit obligations:          
Benefit obligations — beginning of year     4,248 4,571  
Service cost     28 28 $ 31
Interest cost     210 218 235
Plan amendments     0 0  
Actuarial loss (gain)     78 (165)  
Benefits paid     (435) (429)  
Participant contributions     0 0  
Acquired through business combinations     0 35  
Effect of settlement     0 (9)  
Special termination benefits 0 0      
Other     2 (1)  
Benefit obligations — end of year 4,131 4,248 4,131 4,248 4,571
Change in plan assets:          
Fair value of plan assets — beginning of year     4,237 4,282  
Actual return on plan assets     475 254  
Participant contributions     0 0  
Employer contributions     68 119  
Benefits paid     (435) (429)  
Acquired through business combinations     0 21  
Effect of settlement     0 (9)  
Other     1 (1)  
Fair value of plan assets — end of year 4,346 4,237 4,346 4,237 4,282
Funded status 215 (11) 215 (11)  
Amounts recognized in Statements of Financial Position:          
Pension and OPEB assets 287 239 287 239  
Current liabilities (14) (7) (14) (7)  
Non-current liabilities (58) (243) (58) (243)  
Total amount recognized 215 (11) 215 (11)  
Amounts recognized in accumulated other comprehensive loss (income):          
Net actuarial gain (472) (400) (472) (400)  
Prior service cost (credit) 72 89 72 89  
Net amount recognized (400) (311) (400) (311)  
OPEB          
Change in benefit obligations:          
Benefit obligations — beginning of year     1,147 1,036  
Service cost     8 8 10
Interest cost     58 50 64
Plan amendments     3 7  
Actuarial loss (gain)     181 162  
Benefits paid     (161) (155)  
Participant contributions     33 36  
Acquired through business combinations     0 0  
Effect of settlement     0 0  
Special termination benefits     7 2  
Other     1 1  
Benefit obligations — end of year 1,277 1,147 1,277 1,147 1,036
Change in plan assets:          
Fair value of plan assets — beginning of year     742 739  
Actual return on plan assets     63 46  
Participant contributions     33 36  
Employer contributions     86 76  
Benefits paid     (161) (155)  
Acquired through business combinations     0 0  
Effect of settlement     0 0  
Other     0 0  
Fair value of plan assets — end of year 763 742 763 742 $ 739
Funded status (514) (405) (514) (405)  
Amounts recognized in Statements of Financial Position:          
Pension and OPEB assets 182 188 182 188  
Current liabilities (99) (85) (99) (85)  
Non-current liabilities (597) (508) (597) (508)  
Total amount recognized (514) (405) (514) (405)  
Amounts recognized in accumulated other comprehensive loss (income):          
Net actuarial gain (1,426) (1,720) (1,426) (1,720)  
Prior service cost (credit) (92) (109) (92) (109)  
Net amount recognized $ (1,518) $ (1,829) $ (1,518) $ (1,829)