v3.25.2
Employee Benefits - Additional Information (Details) - USD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Mar. 31, 2023
Disclosure Of Defined Benefit Plans [Line Items]      
Sensitivity analysis Sensitivity to significant actuarial assumptions is computed by varying one actuarial assumption used for the valuation of the defined benefit obligation and keeping all other actuarial assumptions constant. In practice, this is not probable, and changes in some of the assumptions may be correlated.    
Gratuity      
Disclosure Of Defined Benefit Plans [Line Items]      
Actual return $ 20 $ 17 $ 17
Expected contribution to pension 43    
Amount contributed under benefit plan 39 37 34
Pension      
Disclosure Of Defined Benefit Plans [Line Items]      
Actual return 9 4 (10)
Expected contribution to pension 5    
Amount contributed under benefit plan 6 2 5
Superannuation      
Disclosure Of Defined Benefit Plans [Line Items]      
Defined contribution plans 61 62 60
Provident Fund      
Disclosure Of Defined Benefit Plans [Line Items]      
Amount contributed under benefit plan 156 $ 152 $ 148
Impact of defined benefit obligation from 0.25% increase in expected rate of returns on plan assets $ 15    
Percentage of increase/decrease in expected rate of returns on plan assets that impact defined benefit obligation by $12 million and $15 million 0.25%