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Stock and Stock-Based Incentive Plans Stock and Stock-Based Incentive Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	May 31, 2018	Feb. 28, 2018	May 31, 2017
Share Repurchase Program
Stock and Stock-Based Incentive Plans
Stock Repurchase Program, Authorized Amount	$ 2,750.0
Available for repurchase, as of end of period	$ 809.5		$ 1,408.3
Stock Option
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	7 years
Cash-settled restricted stock units
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,728,000	1,460,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 58.01	$ 59.36
Cash-settled restricted stock units | Maximum
Stock and Stock-Based Incentive Plans
Cash payment per cash settled restricted stock unit	200.00%
Cash-settled restricted stock units | Minimum
Stock and Stock-Based Incentive Plans
Cash payment per cash settled restricted stock unit	75.00%
Stock-settled market stock units
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Market Stock Units Converted To Common Stock Conversion Ratio Number Of Final Trading Days In Vesting Period	40 days
Share-based Compensation Arrangement by Share-based Payment Award, Conversion Ratio Quotient	2
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	519,000	419,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 74.19	$ 74.04
Stock-settled market stock units | Maximum
Stock and Stock-Based Incentive Plans
Stock units converted to common stock for each unit granted	2
Stock-settled market stock units | Minimum
Stock and Stock-Based Incentive Plans
Stock units converted to common stock for each unit granted	0
Stock-settled performance stock units
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	156,680
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 54.80
Stock-settled performance stock units | Maximum
Stock and Stock-Based Incentive Plans
Stock units converted to common stock for each unit granted	2
PSU EBIT threshold for conversion	200.00%
Stock-settled performance stock units | Minimum
Stock and Stock-Based Incentive Plans
Stock units converted to common stock for each unit granted	0
PSU EBIT threshold for conversion	25.00%
Restricted stock awards
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	36,211
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 56.62
Restricted stock awards | Maximum
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Restricted stock awards | Minimum
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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