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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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 16 - Stock-based Compensation (Details Textual) - USD ($)				3 Months Ended												12 Months Ended
	Jan. 13, 2017	Jan. 15, 2016	Jan. 15, 2015	Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2016	May 31, 2016	Feb. 28, 2016	Nov. 30, 2015	Aug. 31, 2015	May 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2008
Allocated Share-based Compensation Expense																$ 34,183,000	$ 29,793,000	$ 26,371,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized				$ 76.90												$ 76.90
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
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 156.77	$ 168.55	$ 141.84
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value																$ 40.68	$ 46.08	$ 41.87
Common Stock, Capital Shares Reserved for Future Issuance				333,172												333,172
Stock Issued During Period, Shares, Employee Stock Purchase Plans																75,372	73,072	63,265
Non Employee Directors Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	23,846	22,559	13,842
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 35.65	$ 31.03	$ 28.18
Common Stock, Capital Shares Reserved for Future Issuance																			250,000
Non Employee Directors Stock Option Plan [Member] \| Malcolm Frank [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	2,104
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
The 2008 Employee Stock Purchase Plan [Member]
Allocated Share-based Compensation Expense																$ 2,100,000	$ 1,900,000	$ 1,500,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 136.34	$ 131.14	$ 122.76
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value																$ 28.16	$ 26.87	$ 24.05
Stock Issued During Period, Shares, Employee Stock Purchase Plans																75,372	73,072	63,265
Non Performance Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				29,650	11,604		671,263		103,903	4,073	513,785	128,090	61,210	25,075	462,913	713,000	622,000	677,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 152.89	$ 171.18	$ 140.49
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				206,417		61,744	22,460	20,911			530,418			137,522		291,000	551,000	138,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 166.29	$ 165.59	$ 148.52
Employee Stock Option [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 165.75	$ 163.05	$ 169.16	$ 152.51	$ 171.22	$ 152.10	$ 150.81	$ 170.21	$ 165.02	$ 159.14	$ 147.05	$ 131.31
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 42.93	$ 42.23	$ 43.81	$ 39.60	$ 47.82	$ 40.57	$ 40.51	$ 46.62	$ 54.10	$ 44.95	$ 43.05	$ 37.67
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				49,473	0	7,843	5,084	3,944	255	0	93,120	5,704	845	38,088	10,225	62,000	97,000	55,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 158.46		$ 161.31	$ 151.63	$ 164.77	$ 146.20		$ 159.46	$ 157.84	$ 152.77	$ 137.83	$ 127.58	$ 158.26	$ 159.64	$ 138.23