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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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Note 16 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended												12 Months Ended
	Jan. 12, 2018	Jan. 13, 2017	Jan. 15, 2016	Aug. 31, 2018	May 31, 2018	Feb. 28, 2018	Nov. 30, 2017	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, 2018	Aug. 31, 2017	Aug. 31, 2016	Dec. 19, 2017	Aug. 31, 2015
Allocated Share-based Compensation Expense, Total																$ 31,516	$ 34,183	$ 29,793
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total				$ 71,700												$ 71,700
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition																3 years
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount																$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 190.42	$ 156.77	$ 168.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value																$ 48.39	$ 40.68	$ 46.08
Common Stock, Capital Shares Reserved for Future Issuance				268,942												268,942
Stock Issued During Period, Shares, Employee Stock Purchase Plans																64,230	75,372
Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	18,963	23,846	22,559
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 38.76	$ 35.65	$ 31.03
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				282,398				42,000				66,000				282,398	42,000	66,000		88,000
Director Plan [Member] \| Malcolm Frank [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		2,104
Director 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, Total																$ 1,600	$ 2,100	$ 1,900
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 160.34	$ 136.34	$ 131.14
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value																$ 31.83	$ 28.16	$ 26.87
Stock Issued During Period, Shares, Employee Stock Purchase Plans																64,230	75,372	73,072
Non Performance Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				5,848		15,363	553,942	29,650	11,604		671,263	20,911	103,903	4,073	513,785	575,000	713,000	622,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 190.14	$ 152.89	$ 171.18
Employee Stock Option [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 200.20		$ 192.11	$ 189.98	$ 165.75	$ 163.05	$ 169.16	$ 152.51	$ 171.22	$ 152.10	$ 150.81	$ 170.21
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 50.87		$ 48.82	$ 48.27	$ 42.93	$ 42.23	$ 43.81	$ 39.60	$ 47.82	$ 40.57	$ 40.51	$ 46.62
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				16,512						61,744	22,460					17,000	291,000	551,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price																$ 200.20	$ 166.29	$ 165.59
Performance Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross								206,417							530,418
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				2,536	0	0	961	49,473	0	7,843	5,084	3,944	255	0	93,120	3,497	62,400	97,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 191.97			$ 182.17	$ 158.46		$ 161.31	$ 151.63	$ 164.77	$ 146.20		$ 159.46	$ 189.28	$ 158.26	$ 159.64