v3.26.1
Postretirement Benefit Plans - Additional Information (Details) - USD ($)
$ in Millions
3 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Defined Benefit Plan Disclosure [Line Items]    
Net actuarial gains (losses), amortization periods 15 years  
Expected long-term rate of return on plan assets 6.30%  
Maximum amortization period of unfunded actuarial liability 15 years  
Expected additional contribution to funded pension plan $ 22  
Expected additional contribution to unfunded pension plan 15  
Expected additional contribution to savings and defined contribution plans 47  
Pension Benefit Plans    
Defined Benefit Plan Disclosure [Line Items]    
Settlement and curtailment gain 0 $ 0
Other Benefit Plans    
Defined Benefit Plan Disclosure [Line Items]    
Settlement and curtailment gain $ 0 $ 11