v3.26.1
Intangible Assets - Additional Information (Detail)
₨ in Millions, $ in Millions
12 Months Ended
Mar. 31, 2026
INR (₨)
Mar. 31, 2026
USD ($)
Disclosure of detailed information about intangible assets [line items]    
Term of agreement based on which discount rate is applied 25 years 25 years
Impairment loss recognised in profit or loss, intangible assets other than goodwill ₨ 812 $ 9
Ostro Energy Group [member]    
Disclosure of detailed information about intangible assets [line items]    
Impairment loss recognised in profit or loss, intangible assets other than goodwill   $ 812
Bottom of range [member]    
Disclosure of detailed information about intangible assets [line items]    
Term of agreement based on which discount rate is applied 12 years 12 years
Top of range [member]    
Disclosure of detailed information about intangible assets [line items]    
Term of agreement based on which discount rate is applied 18 years 18 years