v3.26.1
Concentrations of credit risk - Exposures to Ten Largest Borrowers Computed as per RBI Guidelines, Based on Higher of Outstanding Balance or Limit on Loans, Investments (Including Credit Substitutes) and Non-Funded Exposures (Detail)
₨ in Millions, $ in Millions
 12 Months Ended
Mar. 31, 2026
INR (₨)
Mar. 31, 2026
USD ($)
Mar. 31, 2025
INR (₨)
Concentration Risk [Line Items]      
Total Exposure ₨ 35,398,542.7 $ 377,262.5 ₨ 31,442,082.5
Borrower 1      
Concentration Risk [Line Items]      
Total Exposure 386,797.9 4,122.3 265,155.5
Borrower 1 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 261,303.1   263,155.5
Borrower 1 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 125,494.8   2,000.0
Borrower 2      
Concentration Risk [Line Items]      
Total Exposure 379,029.0 4,039.5 234,939.9
Borrower 2 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 377,029.0   234,939.9
Borrower 2 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 2,000.0   0.0
Borrower 3      
Concentration Risk [Line Items]      
Total Exposure 241,072.6 2,569.2 228,114.3
Borrower 3 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 240,680.4   227,914.3
Borrower 3 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 392.2   200.0
Borrower 4      
Concentration Risk [Line Items]      
Total Exposure 237,089.9 2,526.8 225,131.7
Borrower 4 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 237,089.9   225,131.7
Borrower 4 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 0.0   0.0
Borrower 5      
Concentration Risk [Line Items]      
Total Exposure 215,290.3 2,294.5 207,225.5
Borrower 5 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 215,290.3   205,523.2
Borrower 5 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 0.0   1,702.3
Borrower 6      
Concentration Risk [Line Items]      
Total Exposure 213,530.4 2,275.7 182,922.5
Borrower 6 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 213,330.4   91,969.7
Borrower 6 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 200.0   90,952.8
Borrower 7      
Concentration Risk [Line Items]      
Total Exposure 195,446.8 2,083.0 176,032.0
Borrower 7 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 195,446.8   176,019.5
Borrower 7 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 0.0   12.5
Borrower 8      
Concentration Risk [Line Items]      
Total Exposure 182,036.8 1,940.1 173,811.1
Borrower 8 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 96,019.9   168,639.0
Borrower 8 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 86,016.9   5,172.1
Borrower 9      
Concentration Risk [Line Items]      
Total Exposure 175,455.7 1,869.9 164,937.1
Borrower 9 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 175,444.8   63,492.5
Borrower 9 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 10.9   101,444.6
Borrower 10      
Concentration Risk [Line Items]      
Total Exposure 175,000.0 $ 1,865.1 154,882.6
Borrower 10 | Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure 175,000.0   153,855.0
Borrower 10 | Non-Funded Exposure      
Concentration Risk [Line Items]      
Total Exposure ₨ 0.0   ₨ 1,027.6