Banks purchase of loans from principal owner.

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Percentage of capital acquired through amalgamation.

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Nominal or face amount used to calculate payment on derivative.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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Amount of cash outflow to acquire investments classified as other.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Amount of cash inflow from the sale of investments classified as other.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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Related Party Transactions - Additional Information (Detail) ₨ in Millions, $ in Millions		12 Months Ended
	Jul. 01, 2023	Mar. 31, 2025 INR (₨)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 INR (₨)	Mar. 31, 2023 INR (₨)	Mar. 31, 2025 USD ($)
Related Party Transaction [Line Items]
Purchase of investments from others		₨ 0.0		₨ 316.7
Sale of investments from others		10,131.7		8,859.5
Proceeds from issuance of long-term debt		661,226.3	$ 7,740.0	1,155,775.2	₨ 1,022,933.1
Dividend paid to principal owner		158,058.1	$ 1,850.1	86,617.1	₨ 86,394.3
Foreign exchange and derivative contracts, notional principal amount		24,496,285.6		21,269,897.6		$ 286,741.0
Bank guarantees		2,462,279.4		1,973,917.9		$ 28,822.2
Percentage of Capital Acquired through amalgamation	100.00%
Tier II bonds
Related Party Transaction [Line Items]
Proceeds from issuance of long-term debt		12,191.0		10,241.0
Principal Owner
Related Party Transaction [Line Items]
Loans purchased from principal owner		0.0		116,320.0
Dividend paid to principal owner		0.0		0.0
Foreign exchange and derivative contracts, notional principal amount		0.0		0.0
Foreign exchange and derivative contracts, mark to market gains		0.0		0.0
Bank guarantees		0.0		0.0
Principal Owner \| Property Plant and equipment
Related Party Transaction [Line Items]
Fixed assets purchased from related parties		2.9		0.0
Others
Related Party Transaction [Line Items]
Bank guarantees		₨ 2.5		₨ 2.5