Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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

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

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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 remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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

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Stock-Based Compensation Outstanding Stock Options (Details 2) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Stock based compensation disclosure
Allocated Share-based Compensation Expense	$ 66,245	$ 66,488	$ 58,983
Employee Stock Option
Stock based compensation disclosure
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	14,351	6,064	168
Allocated Share-based Compensation Expense	11,584	13,530	10,979
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	4,681	5,244	4,293
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	4,432	4,801	5,361	5,624
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 39.58	$ 43.02	$ 53.13	$ 57.78
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	918	1,215	966
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 47.65	$ 33.64	$ 23.72
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(694)	(804)	(25)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 30.75	$ 30.52	$ 21.80
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	(593)	(971)	(1,204)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price	$ 90.31	$ 97.49	$ 51.87
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 85,351
Range of exercise price, 14.81 - 25.00 [Member] \| Employee Stock Option
Stock based compensation disclosure
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	4 years 266 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	710
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 22.80
Range of exercise price, 25.01 - 35.00 [Member] \| Employee Stock Option
Stock based compensation disclosure
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	4 years 95 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	1,873
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 31.91
Range of exercise price, 35.01 - 94.00 [Member] \| Employee Stock Option
Stock based compensation disclosure
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	6 years 266 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	1,495
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 42.67
Range of exercise price, 94.01 - 122.93 [Member] \| Employee Stock Option
Stock based compensation disclosure
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	0 years 113 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	354
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 100.77