v3.26.1
Right of use assets - (Details Textual) - INR (₨)
₨ in Millions
12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Disclosure of quantitative information about right-of-use assets [line items]    
Discount rate used for computation of right-of-use assets 9.50%  
Lease commitments ₨ 0 ₨ 0
Bottom of range [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease agreements escalation rate 0.00%  
Lease agreements escalation intervals period 11 months  
Bottom of range [member] | Land [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease term 30 years  
Bottom of range [member] | Buildings [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease term 1 year 6 months  
Bottom of range [member] | P&M [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease term 2 years  
Top of range [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease agreements escalation rate 20.00%  
Lease agreements escalation intervals period 6 years  
Top of range [member] | Land [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease term 90 years  
Top of range [member] | Buildings [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease term 50 years 9 months 18 days  
Top of range [member] | P&M [member]    
Disclosure of quantitative information about right-of-use assets [line items]    
Lease term 20 years