Earnings Per Share - Narrative (Details) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended		26 Months Ended
	Oct. 05, 2018	Aug. 31, 2018	Aug. 31, 2017	Oct. 05, 2018	Aug. 02, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Basic earnings from discontinued operations (in dollars per share)		$ 0.00	$ 0.52
Diluted earnings from discontinued operations (in dollars per share)		$ 0.00	$ 0.51
Options granted and excluded from the computation of diluted earnings per share (in shares)		0.3	0.6
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)		$ 204.39
Total purchase price of shares repurchased		$ 61,000,000
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
Shares acquired (in shares)		0.4
Stock purchased under share buyback, average price per share (in dollars per share)		$ 200.97
Total purchase price of shares repurchased		$ 78,500,000
Subsequent Event | Share Buyback Program, August 2, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares acquired (in shares)	0.8			1.7
Stock purchased under share buyback, average price per share (in dollars per share)	$ 198.35			$ 191.36
Total purchase price of shares repurchased	$ 156,300,000			$ 324,700,000