Aggregate Notional Principal Amounts of Bank's Outstanding Forward Exchange and Derivative Contracts (Detail) ₨ in Millions, $ in Millions	Mar. 31, 2021 INR (₨)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 INR (₨)
Derivatives, Fair Value [Line Items]
Notional	₨ 8,580,508.8	$ 117,316.3	₨ 10,230,668.8
Gross Assets	84,406.7	1,154.0	190,537.6
Gross Liabilities	81,880.0	1,119.5	184,783.0
Net Fair Value	2,526.7	34.5	5,754.6
Interest rate derivatives
Derivatives, Fair Value [Line Items]
Notional	3,155,410.2	43,142.1	3,644,495.8
Gross Assets	32,217.2		49,876.8
Gross Liabilities	33,894.0		51,976.9
Net Fair Value	(1,676.8)	(22.9)	(2,100.1)
Forward rate agreements
Derivatives, Fair Value [Line Items]
Notional	20,887.8	285.6	0.0
Gross Assets	270.0		0.0
Gross Liabilities	64.1		0.0
Net Fair Value	205.9	2.8	0.0
Currency options
Derivatives, Fair Value [Line Items]
Notional	202,402.7	2,767.3	304,252.4
Gross Assets	1,078.7		3,034.4
Gross Liabilities	1,510.7		4,342.0
Net Fair Value	(432.0)	(5.9)	(1,307.6)
Currency swaps
Derivatives, Fair Value [Line Items]
Notional	237,081.5	3,241.5	202,725.6
Gross Assets	8,126.4		12,396.0
Gross Liabilities	4,940.8		6,592.1
Net Fair Value	3,185.6	43.6	5,803.9
Forward exchange contracts
Derivatives, Fair Value [Line Items]
Notional	4,964,726.6	67,879.8	6,079,195.0
Gross Assets	42,714.4		125,230.4
Gross Liabilities	41,470.4		121,872.0
Net Fair Value	₨ 1,244.0	$ 16.9	₨ 3,358.4

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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