v3.25.2
Retirement benefits - Funded Status of Pension Plan and Amounts Recognized in Bank's Financial Statements (Detail) - Pension
₨ in Millions, $ in Millions
12 Months Ended
Mar. 31, 2025
INR (₨)
Mar. 31, 2025
USD ($)
Mar. 31, 2024
INR (₨)
Mar. 31, 2023
INR (₨)
Mar. 31, 2025
USD ($)
Change in benefit obligations:          
Projected benefit obligation ("PBO"), beginning of the period ₨ 987.3 $ 11.6 ₨ 1,018.0    
Plan amendment (prior service cost) 0.0 0.0 0.0    
Service cost 28.4 0.3 16.0    
Interest cost 71.6 0.8 76.4 ₨ 57.3  
Actuarial (gains)/losses 274.7 3.2 (24.6)    
Benefits paid (111.7) (1.3) (98.5)    
Projected benefit obligation, end of the period 1,250.3 14.6 987.3 1,018.0  
Change in plan assets:          
Fair value of plan assets, beginning of the period 161.5 1.9 3.0    
Expected return on plan assets 10.5 0.1 6.5 0.4  
Actuarial gains/(losses) 1.3 0.0 8.8    
Actual return on plan assets 11.8 0.1 15.3    
Employer contributions 99.9 1.2 241.7    
Benefits paid (111.7) (1.3) (98.5)    
Fair value of plan assets, end of the period 161.5 $ 1.9 161.5 ₨ 3.0  
Funded Status ₨ (1,088.8)   ₨ (825.8)   $ (12.7)