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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

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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- Definition

Per diluted 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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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Earnings per Share - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands	12 Months Ended
	May 31, 2017	May 31, 2016	May 31, 2015	Aug. 06, 2016	Aug. 04, 2015	Jan. 13, 2015	Jul. 30, 2013
Earnings Per Share, Basic and Diluted [Line Items]
Basic earnings per share, discontinued operations (dollars per share)	$ 0.22	$ 2.22	$ 0.24
Diluted earnings per share, discontinued operations (dollars per share)	$ 0.21	$ 2.19	$ 0.24
Options granted excluded from the computation of diluted earnings per share (shares)	600	500	600
Total purchase price of shares repurchased	$ 20,724,000	$ 780,151,000	$ 551,970,000
Employee Payroll Taxes Due on Restricted Stock Awards
Earnings Per Share, Basic and Diluted [Line Items]
Stock purchased under share buyback	200	200
Avg. Price per Share (in dollars per share)	$ 101.37	$ 86.07
Total purchase price of shares repurchased	$ 17,000,000	$ 20,900,000
July 30, 2013
Earnings Per Share, Basic and Diluted [Line Items]
Share buyback program, authorized amount							$ 500,000,000.0
Stock purchased under share buyback	0	0	3,981
Avg. Price per Share (in dollars per share)	$ 0.00	$ 0.00	$ 75.49
Total purchase price of shares repurchased	$ 0	$ 0	$ 300,500,000
January 13, 2015
Earnings Per Share, Basic and Diluted [Line Items]
Share buyback program, authorized amount						$ 500,000,000.0
Stock purchased under share buyback	0	3,078	2,870
Avg. Price per Share (in dollars per share)	$ 0.00	$ 85.44	$ 82.60
Total purchase price of shares repurchased	$ 0	$ 262,928,000	$ 237,072,000
August 4, 2015
Earnings Per Share, Basic and Diluted [Line Items]
Share buyback program, authorized amount					$ 500,000,000.0
Stock purchased under share buyback	39	5,649	0
Avg. Price per Share (in dollars per share)	$ 94.09	$ 87.85	$ 0.00
Total purchase price of shares repurchased	$ 3,691,000	$ 496,309,000	$ 0
August 6, 2016
Earnings Per Share, Basic and Diluted [Line Items]
Share buyback program, authorized amount				$ 500,000,000.0
Stock purchased under share buyback	0	0	0
Avg. Price per Share (in dollars per share)	$ 0.00	$ 0.00	$ 0.00
Total purchase price of shares repurchased	$ 0	$ 0	$ 0