v3.25.2
Property, plant and equipment - Summary of Property, plant and equipment (Parenthetical) (Detail)
₨ in Millions, $ in Millions
12 Months Ended
Mar. 31, 2025
INR (₨)
Mar. 31, 2025
USD ($)
Mar. 31, 2024
INR (₨)
Mar. 31, 2023
INR (₨)
Mar. 31, 2025
USD ($)
Apr. 01, 2023
INR (₨)
Mar. 31, 2022
INR (₨)
Disclosure of detailed information about property, plant and equipment [line items]              
Borrowing costs capitalised ₨ 11,873   ₨ 11,938 ₨ 5,477      
Property Plant And Equipments 747,066   678,600 538,355 $ 8,745    
Depreciation, property, plant and equipment ₨ 18,941 $ 222 ₨ 15,628 14,032      
Bottom of range [member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Rate used to determine borrowing costs eligible for capitalisation 6.70% 6.70% 6.70%        
Top of range [member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Rate used to determine borrowing costs eligible for capitalisation 12.00% 12.00% 12.00%        
Gross carrying amount [member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Property Plant And Equipments ₨ 846,856   ₨ 759,854 605,021     ₨ 490,216
Property, plant and equipment subject to operating leases [member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Property Plant And Equipments 11,477   7,381     ₨ 0  
Depreciation, property, plant and equipment 188   35 0      
Property, plant and equipment subject to operating leases [member] | Gross carrying amount [member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Property Plant And Equipments 11,700   7,416     0  
Capital Work In Progress [Member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Property Plant And Equipments 142,040   159,165 113,723 $ 1,663    
Capital Work In Progress [Member] | Gross carrying amount [member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Property Plant And Equipments 142,040   159,165 ₨ 113,723     ₨ 21,979
Capital Work In Progress [Member] | Property, plant and equipment subject to operating leases [member]              
Disclosure of detailed information about property, plant and equipment [line items]              
Property Plant And Equipments ₨ 608   ₨ 3,846     ₨ 0