Financial Instruments - Summary of Activity in Cash Flow Hedging Reserve within Equity Related to all Derivative Instruments Classified as Cash Flow Hedges (Detail) (Parenthetical) - INR (₨) ₨ in Millions |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Disclosure of detailed information about hedges [abstract] | ||
| Net (gain)/loss reclassified to consolidated statement of income on occurrence of hedged transactions under revenues | ₨ 6,093 | ₨ 394 |
| Net (gain)/loss reclassified to consolidated statement of income on occurrence of hedged transactions under cost of revenues | (877) | (51) |
| Net (gain)/loss reclassified to consolidated statement of income on occurrence of hedged transactions under finance expenses | (53) | (213) |
| Net (gain)/loss reclassified to consolidated statement of income on occurrence of hedged transactions under finance and other income | ₨ 0 | ₨ 73 |