v3.26.1
Share-based Payments - Schedule of Award Activity Related to Stock Incentive Plans (Details) - shares
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
BIP      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
As of beginning of the year (in shares) 1,070,188 1,199,972 1,311,989
Granted (in shares) 423,407 331,999 338,189
Forfeited/expired before vesting (in shares) 0 0 0
Vested (in shares) (540,079) (461,783) (450,206)
Transfer to liability-settled LTIP (in shares) 0 0 0
As of end of the year (in shares) 953,516 1,070,188 1,199,972
ESOP      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
As of beginning of the year (in shares) 665,377 746,762 773,844
Granted (in shares) 290,201 363,868 363,559
Forfeited/expired before vesting (in shares) (57,786) (98,350) (39,545)
Vested (in shares) (323,079) (346,903) (351,096)
Transfer to liability-settled LTIP (in shares) 0 0 0
As of end of the year (in shares) 574,713 665,377 746,762
Equity-Settled LTIP      
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items]      
As of beginning of the year (in shares) 70,266,342 65,410,484 59,752,598
Granted (in shares) 38,351,586 44,722,656 36,531,621
Forfeited/expired before vesting (in shares) (8,366,464) (10,023,316) (4,747,804)
Vested (in shares) (31,949,014) (29,843,482) (25,916,216)
Transfer to liability-settled LTIP (in shares) 0 0 (209,715)
As of end of the year (in shares) 68,302,450 70,266,342 65,410,484