Interest on Loans by Facility (Detail) ₨ in Millions, $ in Millions	12 Months Ended
Mar. 31, 2021 INR (₨)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 INR (₨)	Mar. 31, 2019 INR (₨)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest on loans	₨ 1,017,047.8	$ 13,905.5	₨ 981,794.8	₨ 827,683.0
Wholesale loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest on loans	263,190.7	3,598.5	245,504.7	199,928.0
Retail Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest on loans	₨ 753,857.1	$ 10,307.0	₨ 736,290.1	₨ 627,755.0

The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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Period Type:	duration