Aggregate nominal value of common shares reserved for future issuance

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Period from date of vesting that an equity-based award expires

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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
	Apr. 21, 2017 shares	Apr. 04, 2017 shares	Oct. 20, 2015 shares	Aug. 08, 2015 shares	Mar. 31, 2018 INR (₨) ₨ / shares shares	Mar. 31, 2018 USD ($)	Mar. 31, 2017 INR (₨) ₨ / shares shares	Jul. 31, 2016 INR (₨) shares	Mar. 31, 2016 INR (₨)	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
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, intrinsic value of options exercised at grant date					₨ 28.8		₨ 140.7		₨ 66.7
Stock-based compensation, aggregate intrinsic value of options exercised at exercise date					34,123.2		26,951.4		11,005.5
Stock-based compensation, aggregate intrinsic value of options outstanding at grant date					0.6		28.9
Stock-based compensation, aggregate intrinsic value of options outstanding					63,062.0		49,546.3
Stock-based compensation, aggregate intrinsic value of options exercisable at grant date					0.0		28.9
Stock-based compensation, aggregate intrinsic value of options exercisable					46,092.3		34,213.2
Stock-based compensation, total stock compensation cost recognized under the plans					₨ 6,594.6	$ 101.3	₨ 8,203.2		₨ 12,593.8
Stock-based compensation, unvested options, outstanding \| shares					28,633,550		35,842,300
Stock-based compensation, unvested options, weighted average exercise price \| ₨ / shares					₨ 1,293.5		₨ 1,014.8
Stock-based compensation, unvested options, aggregate intrinsic value at grant date					₨ 0.6		₨ 0.0
Stock-based compensation, unvested options, aggregate intrinsic value as at end of period					16,969.6		15,333.0
Stock-based compensation, total estimated compensation cost to be recognized in future periods					₨ 4,168.8		₨ 3,333.8
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)					7 months 13 days	7 months 13 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															50,000,000
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														50,000,000
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													50,000,000
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												75,000,000
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											100,000,000
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										100,000,000
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								100,000,000
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
Employees' Stock Option Scheme, general discretionary vesting period					3 years	3 years
Employees Stock Option Scheme \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees' Stock Option Scheme, general discretionary vesting period					1 year	1 year
Scheme XXV \| Plan "F"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares				44,833,200
Scheme XXVI \| Plan "F"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares			3,000
Scheme XXVII \| Plan "F"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares		16,865,850
Scheme XXVIII \| Plan "F"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, options granted \| shares	16,200