v3.25.1
Income Taxes (Unrecognized Tax Benefits Reconciliation) (Details) - USD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Mar. 31, 2023
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]      
Beginning balance of unrecognized tax benefits $ 80 $ 73 $ 71
Additions based on tax positions related to the current period 5 9 7
Additions based on tax positions of prior years(1) 6 12 28
Reductions based on tax positions of prior years (2) 17 4 32
Settlements (3) 6 10 0
Foreign exchange 0 0 (1)
Ending Balance of unrecognized tax benefits 68 80 73
Income Tax Details [Line Items]      
Additions based on tax positions related to the current period 5 9 7
Reductions based on tax positions of prior years (2) 17 4 32
Settlements (3) 6 10 0
Germany      
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]      
Additions based on tax positions related to the current period     19
Reductions based on tax positions of prior years (2) 12   24
Settlements (3) 3 10  
Income Tax Details [Line Items]      
Additions based on tax positions related to the current period     19
Reductions based on tax positions of prior years (2) 12   $ 24
Settlements (3) $ 3 $ 10