No authoritative reference available.

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Maximum reduction performance based RSU will be decrease based on total shareholder return

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The maximum number of RSU's an employee may receive as a percentage

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No definition available.

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Please provide definition

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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.

+ References

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Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

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No definition available.

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Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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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.

+ References

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The intrinsic value of equity-based payment equity instruments, excluding stock (or unit) options, that vested during the reporting period as calculated by applying the disclosed pricing methodology.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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

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No definition available.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Note 2 - Stock-Based Compensation (Detail) (USD $)	0 Months Ended		1 Months Ended		3 Months Ended			0 Months Ended	1 Months Ended	3 Months Ended		0 Months Ended	3 Months Ended	1 Months Ended			0 Months Ended	1 Months Ended	0 Months Ended	1 Months Ended	3 Months Ended
Note 2 - Stock-Based Compensation (Detail) (USD $)	Feb. 05, 2013	Feb. 14, 2012	Feb. 28, 2011	Feb. 25, 2010	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Stock Options [Member]	Feb. 05, 2013 Performance Based Restricted Stock Unit [Member]	Apr. 24, 2012 Performance Based Restricted Stock Unit [Member]	Mar. 31, 2013 Performance Based Restricted Stock Unit [Member]	Mar. 31, 2012 Performance Based Restricted Stock Unit [Member]	Feb. 05, 2013 Restricted Stock [Member]	Mar. 31, 2013 Restricted Stock [Member]	Apr. 24, 2012 Time Base Restricted Unit [Member]	Feb. 28, 2011 Time Base Restricted Unit [Member]	Feb. 28, 2011 CEO [Member]	Feb. 05, 2013 Executive Restricted Stock Unit [Member]	Feb. 28, 2011 Executive Restricted Stock Unit [Member]	Feb. 05, 2013 Nonexecutive Restrcted Stock Unit [Member]	Apr. 24, 2012 Nonexecutive Restrcted Stock Unit [Member]	Mar. 31, 2013 Share Based Compensation [Member]	Mar. 31, 2012 Share Based Compensation [Member]
Income Tax Expense (Benefit)					$ (204,000)	$ 309,000															$ 47,000	$ 102,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value					5,600,000	2,800,000
Proceeds from Stock Options Exercised					9,800,000	4,000,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options					1,200,000
Share Based Compensation Weighted Average Period Recognized							1 year 292 days						2 years 109 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate					0.00%
Intrinsic Value of Restricted Stock Units Released					8,700,000	2,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Intrinsic Value (in Dollars per share)										$ 43,200,000	$ 36,300,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options					198,000								25,400,000
Increase In Unamortized Compensation Expense					19,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)		413,000		416,000											153,000					344,650
Share Based Compensation Share Based Payment Other Than Options Percentage Allowed	300.00%							300.00%	300.00%							100.00%		300.00%
Performance Level RSU Reduction Percentage			15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)	91,222								125,333			124,211		219,317			293,760		215,433
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	2 years													2 years			2 years
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in Shares)					65,247	97,247
Stock Issued During Period, Value, Employee Stock Purchase Plan					500,000	700,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition					146 days
Proceeds from Stock Plans					$ 1,167,000	$ 1,036,000