Insurance services - Summary of Information Regarding the Estimated Future Amortisation of VOBA Intangibles Over the Next Five Years (Detail) - Mar. 31, 2024 ₨ in Millions, $ in Millions	INR (₨)	USD ($)
Separate Accounts Disclosure [Abstract]
2025	₨ 16,705.3	$ 200.4
2026	14,721.9	176.6
2027	13,016.3	156.2
2028	11,176.1	134.1
2029	₨ 9,539.9	$ 114.5

Amount of amortization for present value of future profits of insurance contract acquired in business combination expected to be recognized during fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 805
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479835/944-805-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482665/350-30-50-2

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- Definition

Amount of amortization for present value of future profits of insurance contract acquired in business combination expected to be recognized during fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of amortization for present value of future profits of insurance contract acquired in business combination expected to be recognized during next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for present value of future profits of insurance contract acquired in business combination expected to be recognized during third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of amortization for present value of future profits of insurance contract acquired in business combination expected to be recognized during second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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