v3.25.2
Pension and Other Postretirement Benefits - Schedule of Components of Periodic Benefit Costs (Details) - USD ($)
$ in Millions
 12 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2023
Pension benefits      
Defined Benefit Plan Disclosure [Line Items]      
Service cost $ 23 $ 27  
Interest cost 57 61  
Pension benefits | Direct Plans      
Defined Benefit Plan Disclosure [Line Items]      
Service cost 23 27 $ 30
Interest cost 57 61 52
Expected return on plan assets (50) (45) (40)
Amortization of deferred losses (gains) 5 12 23
Net periodic benefit costs 35 55 65
Postretirement benefits      
Defined Benefit Plan Disclosure [Line Items]      
Service cost 1 0  
Interest cost 2 2  
Postretirement benefits | Direct Plans      
Defined Benefit Plan Disclosure [Line Items]      
Service cost 1 0 1
Interest cost 2 2 2
Expected return on plan assets 0 0 0
Amortization of deferred losses (gains) (4) (4) (4)
Net periodic benefit costs $ (1) $ (2) $ (1)