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Share-Based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Grant Date, Aggregate Intrinsic Value

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Share-Based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Grant Date, Aggregate Intrinsic Value

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Share-Based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Grant Date, Intrinsic Value

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Grant Date, Intrinsic Value

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Aggregate Intrinsic Value

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Exercise Price

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Aggregate number of common shares reserved for future issuance.

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of noncash expense for share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Number of non-vested options outstanding.

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Stock-Based Compensation - Additional Information (Detail) ₨ / shares in Units, ₨ in Millions, $ in Millions							12 Months Ended
	Mar. 21, 2020 shares	Oct. 19, 2019 shares	Aug. 03, 2019 shares	Feb. 02, 2019 shares	Sep. 29, 2018 shares	Sep. 01, 2018 shares	Mar. 31, 2020 INR (₨) ₨ / shares shares	Mar. 31, 2020 USD ($)	Mar. 31, 2019 INR (₨) ₨ / shares shares	Mar. 31, 2018 INR (₨)	Jul. 31, 2016 INR (₨) shares	Jun. 30, 2013 INR (₨) shares	Jun. 30, 2010 INR (₨) shares	Jun. 30, 2007 INR (₨) shares	Jun. 30, 2005 INR (₨) shares	Jun. 30, 2003 INR (₨) shares	Jan. 31, 2000 INR (₨) shares	Sep. 20, 2019 ₨ / shares shares	Sep. 19, 2019 ₨ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, intrinsic value of options exercised at grant date							₨ 0.0		₨ 0.0	₨ 28.8
Stock-based compensation, aggregate intrinsic value of options exercised at exercise date							13,339.6		33,117.4	34,123.2
Stock-based compensation, aggregate intrinsic value of options outstanding at grant date							0.5		0.6
Stock-based compensation, aggregate intrinsic value of options outstanding							17,418.0		65,091.1
Stock-based compensation, aggregate intrinsic value of options exercisable at grant date							0.4		0.2
Stock-based compensation, aggregate intrinsic value of options exercisable							16,291.8		52,441.6
Stock-based compensation, total stock compensation cost recognized under the plans							₨ 7,476.1	$ 99.2	₨ 5,343.3	₨ 6,594.6
Stock-based compensation, unvested options, outstanding \| shares							78,401,210		56,003,100
Stock-based compensation, unvested options, weighted average exercise price \| ₨ / shares							₨ 1,113.5		₨ 933.6
Stock-based compensation, unvested options, aggregate intrinsic value at grant date							₨ 0.2		₨ 0.3
Stock-based compensation, unvested options, aggregate intrinsic value as at end of period							1,126.2		12,649.5
Stock-based compensation, total estimated compensation cost to be recognized in future periods							₨ 13,294.0		₨ 7,065.9
Equity shares, par value \| ₨ / shares							₨ 1.0		₨ 1.0									₨ 1.0	₨ 2.0
Equity shares, issued \| shares							5,483,286,460		5,446,613,220									5,470,763,894
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity shares, par value \| ₨ / shares																		₨ 2.0
Employees Stock Option Scheme
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, weighted average period of recognition of total compensation cost not yet recognized (in years)							1 year 2 months 15 days	1 year 2 months 15 days
Employees Stock Option Scheme \| Plan ''A''
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, equity shares reserved for issuance \| shares																	100,000,000.0
Employees' Stock Option Scheme, aggregate nominal value of equity shares reserved																	₨ 100.0
Employees Stock Option Scheme \| Plan ''B''
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, equity shares reserved for issuance \| shares																100,000,000.0
Employees' Stock Option Scheme, aggregate nominal value of equity shares reserved																₨ 100.0
Employees Stock Option Scheme \| Plan ''C''
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, equity shares reserved for issuance \| shares															100,000,000.0
Employees' Stock Option Scheme, aggregate nominal value of equity shares reserved															₨ 100.0
Employees Stock Option Scheme \| Plan ''D''
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, equity shares reserved for issuance \| shares														150,000,000.0
Employees' Stock Option Scheme, aggregate nominal value of equity shares reserved														₨ 150.0
Employees Stock Option Scheme \| Plan "E"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, equity shares reserved for issuance \| shares													200,000,000.0
Employees' Stock Option Scheme, aggregate nominal value of equity shares reserved													₨ 200.0
Employees Stock Option Scheme \| Plan "F"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, equity shares reserved for issuance \| shares												200,000,000.0
Employees' Stock Option Scheme, aggregate nominal value of equity shares reserved												₨ 200.0
Employees Stock Option Scheme \| Plan "G"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, equity shares reserved for issuance \| shares											200,000,000.0
Employees' Stock Option Scheme, aggregate nominal value of equity shares reserved											₨ 200.0
Employees Stock Option Scheme \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, expiration							5 years	5 years
Scheme XXIX \| Plan "G"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares						38,238,000
Scheme XXX \| Plan "G"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares					880,000
Scheme XXXI \| Plan "G"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares				672,000
Scheme XXXII \| Plan "G"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares			578,000
Scheme XXXIII \| Plan "G"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares		46,175,200
Scheme XXXIV \| Plan "G"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares	1,020,400