v3.26.1
Investments - Schedule of Investment (Detail)
₨ in Millions, $ in Millions
Mar. 31, 2026
INR (₨)
Mar. 31, 2026
USD ($)
Mar. 31, 2025
INR (₨)
Disclosure of detailed information about financial instruments [line items]      
Non current investments other than investments accounted for using equity method ₨ 28,053 $ 299 ₨ 26,458
Current Investments 437,680 $ 4,665 411,474
Total 465,733   437,932
Financial instruments at FVTOCI      
Financial instruments at FVTOCI 256,031   266,529
Financial instruments at amortized cost      
Inter corporate and term deposits 121,366   76,169
Financial instruments at FVTPL      
Financial instruments at FVTPL 88,336   95,234
Non-current assets [member]      
Disclosure of detailed information about financial instruments [line items]      
Non current investments other than investments accounted for using equity method 28,053   26,458
Current Assets [member]      
Disclosure of detailed information about financial instruments [line items]      
Current Investments 437,680   411,474
Equity instruments [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 0   0
Equity instruments [member] | Non-current assets [member]      
Financial instruments at FVTOCI      
Financial instruments at FVTOCI [1] 12,143   12,493
Financial instruments at FVTPL      
Financial instruments at FVTPL [1] 7,336   4,955
Inter corporate and term deposits [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 121,366   76,169
Inter corporate and term deposits [member] | Non-current assets [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits [2] 8,574   7,807
Inter corporate and term deposits [member] | Current Assets [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits [2] 112,792   68,362
Fixed maturity plan mutual funds [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 0   0
Fixed maturity plan mutual funds [member] | Non-current assets [member]      
Financial instruments at FVTPL      
Financial instruments at FVTPL 0   1,203
Fixed maturity plan mutual funds [member] | Current Assets [member]      
Financial instruments at FVTPL      
Financial instruments at FVTPL 1,281   300
Short-term mutual funds [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 0   0
Short-term mutual funds [member] | Current Assets [member]      
Financial instruments at FVTPL      
Financial instruments at FVTPL [3] 79,719   88,776
Non-convertible debentures [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 0   0
Non-convertible debentures [member] | Current Assets [member]      
Financial instruments at FVTOCI      
Financial instruments at FVTOCI 210,328   219,389
Government securities [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 0   0
Government securities [member] | Current Assets [member]      
Financial instruments at FVTOCI      
Financial instruments at FVTOCI 8,948   10,651
Commercial papers [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 0   0
Commercial papers [member] | Current Assets [member]      
Financial instruments at FVTOCI      
Financial instruments at FVTOCI 14,227   2,858
Bonds [member]      
Financial instruments at amortized cost      
Inter corporate and term deposits 0   0
Bonds [member] | Current Assets [member]      
Financial instruments at FVTOCI      
Financial instruments at FVTOCI ₨ 10,385   ₨ 21,138
[1] Uncalled capital commitments outstanding as at March 31, 2025 and 2026, was ₹ 1,576 and ₹ 2,577, respectively.
[2] These deposits earn a fixed rate of interest. As at March 31, 2025 and 2026, term deposits include deposits in lien with banks, held as margin money deposits against guarantees amounting to ₹ 953 and ₹ 961, respectively.
[3] As at March 31, 2025 and 2026, short-term mutual funds include units placed on lien with bank on account of margin money for currency derivatives amounting to ₹ 233 and ₹ Nil, respectively.