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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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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.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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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 vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Price of a single share of a number of saleable stocks of a company.

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Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Purchase price of common stock expressed as a percentage of its fair value.

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Note 13 - Employee Stock Option and Retirement Plans (Details Textual) - USD ($)				1 Months Ended	3 Months Ended			6 Months Ended		18 Months Ended
	Feb. 09, 2019	Dec. 19, 2017	Nov. 01, 2013	Jun. 30, 2017	Feb. 28, 2019	Nov. 30, 2018	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Aug. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance					3,216,000	3,457,000		3,216,000		3,216,000	3,143,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance					$ 164.42	$ 162.68		$ 164.42		$ 164.42	$ 153.05
Share Price					$ 235.17			$ 235.17		$ 235.17
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total					$ 87,200,000			$ 87,200,000		$ 87,200,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					3 years 109 days
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent					85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate					10.00%			10.00%		10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Contribution Limit					$ 25,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans					12,624		14,805	25,719		34,394
Treasury Stock Acquired, Average Cost Per Share					$ 199.36		$ 171.23	$ 198.33		$ 150.25
Common Stock, Capital Shares Reserved for Future Issuance					243,223			243,223		243,223
Defined Contribution Plan, Employer Discretionary Contribution Amount					$ 2,600,000		$ 2,600,000	$ 5,200,000	$ 5,500,000
LTIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value					$ 15,500,000		17,200,000	$ 26,300,000	$ 35,200,000
Employee Stock Option [Member] \| LTIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		5 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance					460,713			460,713		460,713
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance					$ 221.74			$ 221.74		$ 221.74
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number					1,200,000			1,200,000		1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price					$ 138.41			$ 138.41		$ 138.41
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value					$ 116,500,000			$ 116,500,000		$ 116,500,000	$ 105,300,000
Employee Stock Option [Member] \| LTIP [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
Performance Shares [Member] \| BI-SAM Technologies [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				206,417
Performance Shares [Member] \| BI-SAM Technologies [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				40.00%				0.00%
Performance Shares [Member] \| BI-SAM Technologies [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage				20.00%				80.00%
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross								41,153
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period						41,000			961
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value						$ 212.66		$ 212.66	$ 182.17
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance					107,000	131,000		107,000		107,000	143,000
Restricted Stock [Member] \| LTIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					5 years
Share Price					$ 235.17			$ 235.17		$ 235.17	$ 229.39
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					41,153
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value					$ 212.66
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance					106,558			106,558		106,558
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total					$ 16,100,000			$ 16,100,000		$ 16,100,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition								3 years 219 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested					25,100,000			$ 25,100,000		$ 25,100,000	$ 32,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Pre-Tax Intrinsic Value					$ 5,100,000		$ 700,000	$ 16,700,000	$ 2,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Share Equivalent					2.5			2.5		2.5
Restricted Stock [Member] \| LTIP [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			60.00%
Restricted Stock [Member] \| LTIP [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			40.00%