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Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.

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Earnings Per Share - Narrative (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended		19 Months Ended	1 Months Ended
	Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2015	Apr. 02, 2015	Jul. 30, 2013	Jan. 13, 2015
Earnings Per Share, Basic and Diluted [Line Items]
Basic earnings per share, discontinued operations (dollars per share)	$ 0.01	$ 0.00	$ 0.16	$ 0.01
Diluted earnings per share, discontinued operations (dollars per share)	$ 0.01	$ 0.00	$ 0.15	$ 0.01
Options granted and excluded from the computation of diluted earnings per share (shares)	0.4	0.4	0.7	0.6
Common stock purchased under share buyback	3.2us-gaap_TreasuryStockSharesAcquired		4.0us-gaap_TreasuryStockSharesAcquired		7.3us-gaap_TreasuryStockSharesAcquired
Common stock purchased under a share buyback, average price per share	$ 78.84		$ 75.49		$ 68.28
Aggregate purchase price of common stock under a share buyback program	$ 250.8		$ 300.5		$ 500.0
Employee payroll taxes due on restricted stock
Earnings Per Share, Basic and Diluted [Line Items]
Common stock purchased under share buyback			0.2
Common stock purchased under a share buyback, average price per share			$ 64.32
Aggregate purchase price of common stock under a share buyback program	0.2		14.1
Common Stock \| Subsequent Event
Earnings Per Share, Basic and Diluted [Line Items]
Common stock purchased under share buyback						0
July 30, 2013
Earnings Per Share, Basic and Diluted [Line Items]
Share buyback program, authorized amount							500.0
January 13, 2015
Earnings Per Share, Basic and Diluted [Line Items]
Share buyback program, authorized amount								$ 500.0