Related party transactions - Balances Payable to Related Parties (Detail) ₨ in Millions, $ in Millions	Mar. 31, 2025 INR (₨)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 INR (₨)
Related Party Transaction [Line Items]
Balances in non-interest-bearing deposits	₨ 3,116,596.7	$ 36,481.3	₨ 3,079,829.4
Balances in interest-bearing deposits	23,994,357.2	280,865.7	20,688,406.2
Principal Owner
Related Party Transaction [Line Items]
Balances in non-interest-bearing deposits	0.0		0.0
Balances in interest-bearing deposits	0.0		0.0
Accrued expenses and other liabilities	0.0		0.0
Total	0.0		0.0
Others
Related Party Transaction [Line Items]
Balances in non-interest-bearing deposits	2,349.0		2,522.6
Balances in interest-bearing deposits	462.6		4,006.3
Accrued expenses and other liabilities	110.8		0.0
Total	2,922.4		6,528.9
Related Party
Related Party Transaction [Line Items]
Balances in non-interest-bearing deposits	2,349.0	27.5	2,522.6
Balances in interest-bearing deposits	462.6	5.4	4,006.3
Accrued expenses and other liabilities	110.8	1.3	0.0
Total	₨ 2,922.4	$ 34.2	₨ 6,528.9

Sum of the carrying values as of the balance sheet date of obligations incurred through that date, including liabilities incurred and payable to vendors for goods and services received, taxes, interest, rent and utilities, compensation costs, payroll taxes and fringe benefits (other than pension and postretirement obligations), contractual rights and obligations, and statutory obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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