v3.25.4
Postretirement Benefit Plans - Additional Information (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2025
Dec. 31, 2024
Defined Benefit Plan Disclosure [Line Items]        
Net actuarial gains (losses), amortization periods     15 years  
Expected long-term rate of return on plan assets     6.50%  
Maximum amortization period of unfunded actuarial liability 15 years      
Expected additional contribution to funded pension plan     $ 6  
Expected additional contribution to unfunded pension plan     6  
Expected additional contribution to savings and defined contribution plans     16  
Pension Benefit Plans        
Defined Benefit Plan Disclosure [Line Items]        
Settlement and curtailment gain $ 1 $ 0 1 $ 0
Amount settled 94      
Payouts 15      
Settlement gain     1  
Other Benefit Plans        
Defined Benefit Plan Disclosure [Line Items]        
Settlement and curtailment gain $ 0 $ 0 $ 11 $ 0