Repurchase and Resell Agreements - Additional Information (Detail) ₨ in Millions, $ in Millions	12 Months Ended
Mar. 31, 2021 INR (₨)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 INR (₨)
Repurchase Agreement and Resale Agreement Counterparty [Line Items]
Securities purchased under agreements to resell	₨ 270,060.0	$ 3,692.4	₨ 250,000.0
Securities sold under repurchase agreements, amount outstanding	₨ 356,059.2	$ 4,868.2	₨ 507,982.0
Maximum
Repurchase Agreement and Resale Agreement Counterparty [Line Items]
Securities purchased under agreements to resell, maturity (days)	14 days
Securities sold under repurchase agreements, maturity (days)	14 days

Repurchase Agreement and Resale Agreement Counterparty [Line Items]

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- Definition

Maximum maturity period generally of amount outstanding borrowed in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price.

+ References

No definition available.

+ Details

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- Definition

Maximum maturity period generally for amount outstanding loaned in the form of a security resale agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price.

+ References

No definition available.

+ Details

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- Definition

Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

+ Details

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- Definition

Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

+ Details

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