Income Taxes - Tax Effects of Significant Temporary Differences (Parenthetical) (Detail) ₨ in Millions	Mar. 31, 2026 INR (₨)
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]
Reversal Of Deferred Tax Liability On Sale Of Subsidiary	₨ 3,375.0
Deferred Tax Assets, Equity Method Investments	₨ 16,453.9

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from equity method investments.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Period Type:	instant