Aggregate number of common shares reserved for future issuance.

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-Paragraph 4

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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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 weighted average fair value at grant date for nonvested equity-based awards issued 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

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

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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 stock options awarded under the plan during the reporting 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 shares issued during the period as a result of an employee stock purchase plan.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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-Name Regulation S-X (SX)

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Total cost of shares repurchased divided by the total number of shares repurchased.

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 1

-Section B

-Paragraph 7

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Note 14. Stock-Based Compensation (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended			3 Months Ended							12 Months Ended	0 Months Ended	3 Months Ended
	Nov. 30, 2011	Nov. 30, 2010	Aug. 31, 2011	Nov. 30, 2011 Non-Performance Based [Member]	Nov. 30, 2010 Non-Performance Based [Member]	May 31, 2011 Employee Stock Purchase Plan [Member]	May 31, 2010 Employee Stock Purchase Plan [Member]	May 31, 2011 Employee Stock Purchase Plan [Member]	Nov. 30, 2010 Employee Stock Purchase Plan [Member]	May 31, 2010 Employee Stock Purchase Plan [Member]	Nov. 08, 2011 November 8, 2010 Restricted Stock [Member]	Nov. 08, 2010 November 8, 2010 Restricted Units [Member]	Nov. 30, 2011 Performance Based [Member]	Nov. 30, 2010 Performance Based [Member]	May 31, 2011 Non-Employee Directors' Stock Option Plan [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized (in Dollars)	$ 53,800
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	3.5
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures (in Shares)				419,593	84,811								665,551	809,239
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 94.84			$ 94.84	$ 88.40								$ 94.84	$ 88.40
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 32.08	$ 24.42		$ 32.08	$ 24.42								$ 32.08	$ 24.42
Common Stock, Capital Shares Reserved for Future Issuance (in Shares)								257,372							250,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)											117,723	3,291
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 71.31		$ 71.31								$ 84.38	$ 83.49
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in Shares)	209,000	626,000				23,166	21,734	23,166		21,734
Treasury Stock Acquired, Average Cost Per Share						$ 73.66	$ 64.91	$ 73.66		$ 64.91
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value									$ 12.63	$ 15.46