Group information - Consolidated Statement of Cash Flows (Details) ₨ in Millions, $ in Millions	12 Months Ended
Mar. 31, 2026 INR (₨)	Mar. 31, 2026 USD ($)	Mar. 31, 2025 INR (₨)	Mar. 31, 2024 INR (₨)
Disclosure of associates [line items]
Net cash generated from operating activities	₨ 85,439	$ 911	₨ 69,787	₨ 72,225
Net cash used in investing activities	(102,752)	(1,095)	(74,164)	(162,535)
Net cash generated from financing activities	2,550	27	19,984	₨ 82,417
RPPL
Disclosure of associates [line items]
Net cash generated from operating activities	82,034	874	68,949
Net cash used in investing activities	(118,554)	(1,263)	(74,327)
Net cash generated from financing activities	17,986	192	19,679
Net increase/ (decrease) in cash and cash equivalents	₨ (18,534)	$ (198)	₨ 14,301

The cash flows from (used in) financing activities, which are activities that result in changes in the size and composition of the contributed equity and borrowings of the entity, from continuing and discontinued operations.

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The cash flows from (used in) investing activities, which are the acquisition and disposal of long-term assets and other investments not included in cash equivalents, from continuing and discontinued operations.

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The increase (decrease) in cash and cash equivalents after the effect of exchange rate changes on cash and cash equivalents held in foreign currencies. [Refer: Cash and cash equivalents; Effect of exchange rate changes on cash and cash equivalents]

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