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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Aggregate number of common shares reserved for future issuance.

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

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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 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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of share options (or share units) granted during the 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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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 15 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended						9 Months Ended		12 Months Ended
	Jan. 13, 2017	Jan. 15, 2016	Jul. 31, 2012	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	May 31, 2016	Feb. 29, 2016	Nov. 30, 2015	May 31, 2017	May 31, 2016	Aug. 31, 2016	Aug. 31, 2008
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition										3 years 109 days
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount										$ 0		$ 0
Common Stock, Capital Shares Reserved for Future Issuance				353,990						353,990
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 42.23			$ 40.57			$ 39.98	$ 46.05
Stock Issued During Period, Shares, Employee Stock Purchase Plans				17,314			17,538			54,554	53,711
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 163.05			$ 152.10			$ 154.01	$ 168.51
Allocated Share-based Compensation Expense				$ 7,300			$ 7,400			$ 20,900	$ 22,400
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized				$ 76,100						$ 76,100
Non Employee Directors Stock Option Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance													250,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				42,185	42,000	66,000				42,185		66,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	23,846	22,559
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 35.65	$ 31.03
Non Employee Directors Stock Option Plan [Member] \| Malcolm Frank [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	2,417
Non Employee Directors Stock Option Plan [Member] \| Laurie Siegel [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		2,417
Non Employee Directors Stock Option Plan [Member] \| Sheila B. Jordan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	2,417
The 2008 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 29.84			$ 26.07			$ 28.48	$ 27.19
Stock Issued During Period, Shares, Employee Stock Purchase Plans				17,314			17,538			54,554	53,711
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 140.84			$ 131.57			$ 137.38	$ 129.83
Allocated Share-based Compensation Expense				$ 500			$ 400			$ 1,500	$ 1,400
Non Performance Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				11,604		671,263	103,903	4,073	513,785
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 163.05		$ 152.28
Performance Shares [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition										73 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			241,546		61,744	22,460			530,418
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price					$ 169.16	$ 159.45
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized				$ 100						$ 100
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 42.23	43.81	39.60	$ 40.57	$ 40.51
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 163.05	$ 169.16	$ 152.51	$ 152.10	$ 150.81
Performance and Non Performance [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value									$ 46.62
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price									$ 170.21
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					8,000	5,000				12,927	93,375
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value					$ 161.31	$ 151.63				$ 157.50	$ 159.42