v3.26.1
Retirement benefits - Net Gratuity Cost (Detail)
₨ in Millions, $ in Millions
12 Months Ended
Mar. 31, 2026
INR (₨)
Mar. 31, 2026
USD ($)
Mar. 31, 2025
INR (₨)
Mar. 31, 2024
INR (₨)
Defined Benefit Plan Disclosure [Line Items]        
Past service cost amortized ₨ 1,011.3 $ 10.8    
Gratuity        
Defined Benefit Plan Disclosure [Line Items]        
Service cost 3,717.2 39.6 ₨ 3,213.5 ₨ 1,968.8
Interest cost 1,551.2 16.5 1,313.5 981.3
Past service cost amortized 1,114.9 11.9 0.0 0.0
(Gains)/Losses on Curtailment (223.6) (2.4) 0.0 0.0
Expected return on plan assets (1,340.3) (14.3) (1,283.4) (1,036.1)
Actuarial (gains)/losses (38.1) (0.4) 374.2 (3,196.5)
Net gratuity cost ₨ 4,781.3 $ 50.9 ₨ 3,617.8 ₨ (1,282.5)