v3.26.1
Employee Benefits - Additional Information (Details) - USD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
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 $ 27 $ 20 $ 17
Expected contribution to pension 57    
Amount contributed under benefit plan 184 39 37
Pension      
Disclosure Of Defined Benefit Plans [Line Items]      
Actual return 10 9 4
Expected contribution to pension 7    
Amount contributed under benefit plan 6 6 2
Superannuation      
Disclosure Of Defined Benefit Plans [Line Items]      
Defined contribution plans 65 61 62
Provident Fund      
Disclosure Of Defined Benefit Plans [Line Items]      
Amount contributed under benefit plan 171 $ 156 $ 152
Impact of defined benefit obligation from 0.25% increase in expected rate of returns on plan assets 8    
Impact of defined benefit obligation from 0.25% decrease in expected rate of returns on plan assets $ 16    
Percentage of increase/decrease in expected rate of returns on plan assets that impact defined benefit obligation by $9 million and $18 million 0.25%