v3.25.2
Stock - Stock Options Outstanding, Employees Stock Option Schemes (Detail) - Employee Stock Option
12 Months Ended
Mar. 31, 2025
₨ / shares
shares
Mar. 31, 2025
$ / shares
₨ / shares
shares
Mar. 31, 2024
₨ / shares
shares
Mar. 31, 2023
₨ / shares
shares
Mar. 31, 2022
₨ / shares
shares
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]          
Number Of Shares Arising Out Of Options | shares 141,374,510 141,374,510 175,659,424 151,682,461 158,106,016
Weighted Average Exercise Price | ₨ / shares ₨ 1,413.25 ₨ 1,413.25 ₨ 1,307.93 ₨ 1,264.86 ₨ 1,175.65
Plan "E"          
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]          
Range of exercise price | (per share) ₨ 1,636.9 ₨ 19.16      
Number Of Shares Arising Out Of Options | shares 4,793,680 4,793,680      
Weighted Average Remaining Life 4 years 11 months 15 days 4 years 11 months 15 days      
Weighted Average Exercise Price | ₨ / shares ₨ 1,636.9 ₨ 1,636.9      
Plan "F"          
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]          
Range of exercise price | (per share) ₨ 1,636.9 ₨ 19.16      
Number Of Shares Arising Out Of Options | shares 11,490,680 11,490,680      
Weighted Average Remaining Life 4 years 11 months 8 days 4 years 11 months 8 days      
Weighted Average Exercise Price | ₨ / shares ₨ 1,636.9 ₨ 1,636.9      
Plan "G"          
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]          
Range of exercise price, Lower Range | (per share) 882.85 ₨ 10.33      
Range of exercise price, Upper Range | (per share) ₨ 1,673.1 ₨ 19.58      
Number Of Shares Arising Out Of Options | shares 74,981,293 74,981,293      
Weighted Average Remaining Life 2 years 5 months 23 days 2 years 5 months 23 days      
Weighted Average Exercise Price | ₨ / shares ₨ 1,360.69 ₨ 1,360.69      
Plan "H"          
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]          
Range of exercise price, Lower Range | (per share) 1,677.3 ₨ 19.63      
Range of exercise price, Upper Range | (per share) ₨ 1,734.2 ₨ 20.3      
Number Of Shares Arising Out Of Options | shares 22,572,860 22,572,860      
Weighted Average Remaining Life 6 years 21 days 6 years 21 days      
Weighted Average Exercise Price | ₨ / shares ₨ 1,733.15 ₨ 1,733.15      
eHDFC [Member]          
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]          
Range of exercise price, Lower Range | (per share) 160.79 ₨ 1.88      
Range of exercise price, Upper Range | (per share) ₨ 1,535.27 ₨ 17.97      
Number Of Shares Arising Out Of Options | shares 27,535,997 27,535,997      
Weighted Average Remaining Life 2 years 6 months 29 days 2 years 6 months 29 days      
Weighted Average Exercise Price | ₨ / shares ₨ 1,139.68 ₨ 1,139.68