Earnings Per Share - Narrative (Details) - USD ($) $ / shares in Units, shares in Millions	3 Months Ended
	Aug. 31, 2017	Aug. 31, 2016	Aug. 02, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Discontinued operations (in dollars per share)	$ 0.52	$ 0.02
Discontinued operations (in dollars per share)	$ 0.51	0.02
Diluted earnings per share from discontinued operations (in dollars per share)		$ 0.02
Options granted and excluded from the computation of diluted earnings per share (in shares)	0.6	0.7
Employee Payroll Taxes Due on Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares acquired (in shares)	0.3
Stock purchased under share buyback, average price per share (in dollars per share)	$ 128.70
Total purchase price of shares repurchased	$ 35,000,000
Share Buyback Program, August 2, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share buyback program, authorized amount			$ 500,000,000.0