v3.26.1
Defined Benefit Plans - Net Periodic Benefit Costs (Details) - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2024
Retirement Benefits [Abstract]          
Service cost     $ 26 $ 19 $ 18
Interest cost     $ 88 58 50
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]     Employee benefit assets    
Expected return on plan assets     $ (97) (61) (57)
Amortization of net loss     3 7 3
Amortization of prior service credit     (2) (3) (4)
Curtailment credit     0 0 (1)
Settlement costs $ (7) $ (2) 13 12 3
Net periodic benefit cost     $ 31 $ 32 $ 12