v3.25.1
Financial Instruments and Commodity Contracts (Details Textual)
gallon in Millions, MMBTU in Millions, $ in Millions
 12 Months Ended
Mar. 31, 2025
USD ($)
gallon
MMBTU
Mar. 31, 2024
USD ($)
gallon
MMBTU
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) $ 68 $ (103)
Expected reclassification of gains (losses) from AOCI to earnings 57  
Derivative Liability 54 117
Derivatives not designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) (3) (35)
Derivatives designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) 71 (68)
Currency exchange contracts | Derivatives not designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) (5) (11)
Derivative, Notional Amount 1,500 1,500
Currency exchange contracts | Derivatives designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative, Notional Amount 261  
Currency exchange contracts | Cash flow hedges    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative, Notional Amount 1,100 1,000
Currency exchange contracts | Cash flow hedges | Derivatives designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) (22) (8)
Interest rate swap contracts | Derivatives designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative, Notional Amount $ 400 400
Derivative, Average Fixed Interest Rate 4.40%  
Interest rate swap contracts | Cash flow hedges | Derivatives designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) $ (5) (2)
Natural Gas Swaps | Derivatives not designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) $ (1) $ (1)
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU 1  
Derivative, Remaining Maturity 1 year 1 year
Natural Gas Swaps | Derivatives designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) $ (5) $ (3)
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU 5 7
Fuel | Derivatives not designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) $ (1) $ (1)
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU 1  
Fuel | Derivatives designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) $ 1  
Derivative, Nonmonetary Notional Amount | gallon 7 6
Derivative, Remaining Maturity 1 year  
Metal forward contracts | Derivatives not designated as hedging instruments:    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative asset (liability) $ (8) $ (6)
Derivative, Remaining Maturity 1 year  
Aluminum Forward Sales Contracts | Derivatives not designated as hedging instruments: | Maximum    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative, Remaining Maturity 1 year  
Aluminum Forward Sales Contracts | Cash flow hedges | Derivatives designated as hedging instruments: | Maximum    
Financial Instruments And Commodity Contracts [Abstract]    
Derivative, Remaining Maturity 3 years