v3.26.1
Pension and Other Postretirement Benefits (Components of Net Periodic Benefit Costs) (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Pension Benefits        
Components of net periodic benefit cost:        
Service cost $ 62 $ 57 $ 124 $ 112
Interest cost 38 35 77 72
Expected return on plan assets (39) (35) (78) (72)
Amortization of prior service credit (2) (2) (4) (4)
Amortization of actuarial loss 5 4 9 8
Net periodic benefit cost 64 60 128 117
Other Benefits        
Components of net periodic benefit cost:        
Service cost 5 5 10 10
Interest cost 9 8 17 17
Amortization of prior service credit (6) (5) (11) (11)
Net periodic benefit cost $ 8 $ 8 $ 16 $ 16