Other investments (Parenthetical) (Details) - Curis, Inc. [Member] - INR (₨) ₨ in Millions	Mar. 31, 2026	Mar. 31, 2025
Other Investments [Line Items]
Non current investments in equity instruments at fair value through other comprehensive income	₨ 2,699
Cumulative unrealized gains losses on equity investments at fair value through other comprehensive income	₨ 2,685	₨ 2,651

The amount of non-current investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: Investments in equity instruments designated at fair value through other comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2025-01-01
-Paragraph 8
-Subparagraph h
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2025-en-r&anchor=para_8_h&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 44
-Subparagraph e
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_44_e_ii&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 44
-Subparagraph e
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_44_e_ii&doctype=Standard
-URIDate 2025-03-27

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