v3.26.1
Financial Instruments - Summary of Offsetting Financial Assets and Financial Liabilities (Detail) - INR (₨)
₨ in Millions
Mar. 31, 2026
Mar. 31, 2025
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized ₨ 249,459 ₨ 206,117
Gross amounts of recognized financial liabilities set off (12,449) (10,681)
Net amounts recognized 237,010 195,436
Gross amounts recognized 129,867 110,604
Gross amounts of recognized financial assets set off (12,449) (10,681)
Net amounts recognized 117,418 99,923
Trade receivables - non-current [member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 349 299
Gross amounts of recognized financial liabilities set off 0 0
Net amounts recognized 349 299
Trade receivables - current [member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 147,371 126,512
Gross amounts of recognized financial liabilities set off (11,470) (8,767)
Net amounts recognized 135,901 117,745
Other financial assets - non-current [member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 6,259 4,664
Gross amounts of recognized financial liabilities set off 0 0
Net amounts recognized 6,259 4,664
Other financial assets - current [member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 10,245 8,448
Gross amounts of recognized financial liabilities set off 0 0
Net amounts recognized 10,245 8,448
Unbilled receivables - non-current [Member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 7,433 0
Gross amounts of recognized financial liabilities set off 0 0
Net amounts recognized 7,433 0
Unbilled receivables - current [Member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 77,802 66,194
Gross amounts of recognized financial liabilities set off (979) (1,914)
Net amounts recognized 76,823 64,280
Accrued expenses - non-current [Member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 4,394 0
Gross amounts of recognized financial assets set off 0 0
Net amounts recognized 4,394 0
Trade payables and accrued expenses - current [Member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 107,373 98,933
Gross amounts of recognized financial assets set off (12,449) (10,681)
Net amounts recognized 94,924 88,252
Other financial liabilities - non-current [member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 6,743 7,793
Gross amounts of recognized financial assets set off 0 0
Net amounts recognized 6,743 7,793
Other financial liabilities - current [member]    
Disclosure of detailed information about financial instruments [line items]    
Gross amounts recognized 11,357 3,878
Gross amounts of recognized financial assets set off 0 0
Net amounts recognized ₨ 11,357 ₨ 3,878