Activity in Options Outstanding under Employee Stock Option Scheme, Employees Stock Option Schemes (Detail) - Employees Stock Option Scheme - ₨ / shares	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Options
Options outstanding, beginning of period	168,168,760	142,865,602	136,612,822
Granted	25,628,600	57,466,600	47,773,600
Exercised	(32,764,494)	(29,490,022)	(36,673,240)
Forfeited	(2,639,100)	(2,032,110)	(4,813,580)
Lapsed	(287,750)	(641,310)	(34,000)
Options outstanding, end of period	158,106,016	168,168,760	142,865,602
Options exercisable, end of period	65,321,116	64,453,260	64,464,392
Weighted Average Exercise Price
Options outstanding, beginning of period	₨ 1,063.79	₨ 899.03	₨ 682.99
Granted	1,427.29	1,235.8	1,220.13
Exercised	796.52	596.85	504.1
Forfeited	1,231.84	1,163.29	965.64
Lapsed	870.34	929.57	568.1
Options outstanding, end of period	1,175.65	1,063.79	899.03
Options exercisable, end of period	1,036.49	834.48	638.18
Weighted average fair value of options granted during the year	₨ 415.12	₨ 320.42	₨ 305.78

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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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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Number of options outstanding, including both vested and non-vested options.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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