Loans - Allowance for Credit Losses (Parenthetical) (Detail) ₨ in Millions, $ in Millions	12 Months Ended
Mar. 31, 2025 INR (₨)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 INR (₨)	Mar. 31, 2023 INR (₨)
Financing Receivable, Allowance for Credit Loss [Line Items]
Cash recoveries, recoveries against write off cases	₨ 46,492.3	$ 544.3	₨ 48,690.9	₨ 56,142.6
Retail loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Recoveries of loans	46,314.2		44,432.2	53,374.2
Wholesale loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Recoveries of loans	₨ 178.1		₨ 4,258.7	₨ 2,768.4

Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

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-Number 229
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of increase in allowance for credit loss on financing receivable from recovery.

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