v3.25.2
Long-Term Debt - Additional Information (Detail)
₨ in Millions, $ in Millions
 12 Months Ended
Mar. 31, 2025
INR (₨)
Mar. 31, 2024
INR (₨)
Mar. 31, 2025
USD ($)
Debt Instrument [Line Items]      
Subordinated debt, debt raised during the year ₨ 8,570.0 ₨ 20,000.0  
Other long term debt, debt raised during the year 652,656.3 1,132,275.2  
Perpetual debt, debt raised during the year 0.0 3,500.0  
Other long-term debt 5,436,429.4 6,244,131.6 $ 63,636.1
Foreign currency borrowings      
Debt Instrument [Line Items]      
Other long-term debt 856,647.3 693,914.0  
Functional currency borrowings      
Debt Instrument [Line Items]      
Other long-term debt ₨ 4,579,782.1 ₨ 5,550,217.6