Stock - Activity in Options Outstanding under Employee Stock Option Scheme, Employees Stock Option Schemes (Detail) - Employee Stock Option - ₨ / shares	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Options
Options outstanding, beginning of period	175,659,424	151,682,461	158,106,016
Addition on account of eHDFC merger	0	48,559,681	0
Granted	23,146,660	24,384,690	30,480,145
Exercised	(52,955,047)	(46,304,966)	(34,201,810)
Forfeited	(3,977,478)	(2,198,002)	(2,175,700)
Lapsed	(499,049)	(464,440)	(526,190)
Options outstanding, end of period	141,374,510	175,659,424	151,682,461
Options exercisable, end of period	81,335,537	98,829,856	65,124,916
Weighted Average Exercise Price
Options outstanding, beginning of period	₨ 1,307.93	₨ 1,264.86	₨ 1,175.65
Addition on account of eHDFC merger	0	1,124.77	0
Granted	1,729.84	1,611.84	1,425.69
Exercised	1,198.42	1,133.72	998.73
Forfeited	1,481.42	1,363.8	1,274.53
Lapsed	1,279.26	1,151.88	1,033.65
Options outstanding, end of period	1,413.25	1,307.93	1,264.86
Options exercisable, end of period	1,279.91	1,201.65	1,162.96
Weighted average fair value of options granted during the year	₨ 656.66	₨ 607.28	₨ 548.11

Share based compensation by share based award options issued on account of business combinations.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average price at which grantees could acquire or could have acquired the underlying shares with respect to any other type of change in shares reserved for issuance.

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Number of share options (or share units) exercised during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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