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Earnings Per Share - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands	1 Months Ended	2 Months Ended	3 Months Ended		6 Months Ended		28 Months Ended
	Jan. 08, 2019	Jan. 08, 2019	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Oct. 30, 2018	Aug. 02, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Basic earnings (loss) from discontinued operations (in dollars per share)			$ 0.00	$ (0.01)	$ 0.00	$ 0.51
Diluted earnings from discontinued operations (in dollars per share)			$ 0.00	$ (0.01)	$ 0.00	$ 0.50
Options granted and excluded from the computation of diluted earnings per share (in shares)			400	500	400	600
Employee Payroll Taxes Due on Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares			100		300
Stock purchased under share buyback, average price per share (in dollars per share)			$ 194.14		$ 204.32
Purchase Price			$ 400,000		$ 61,500,000
August 2, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share buyback program, authorized amount									$ 500,000,000.0
Shares			1,740		2,130		2,600
Stock purchased under share buyback, average price per share (in dollars per share)			$ 190.66		$ 192.55		$ 188.82
Purchase Price			$ 331,547,000		$ 410,003,000		$ 500,000,000
October 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share buyback program, authorized amount								$ 1,000,000,000.0
Shares			201		201
Stock purchased under share buyback, average price per share (in dollars per share)			$ 181.41		$ 181.41
Purchase Price			$ 36,579,000		$ 36,579,000
Subsequent Event \| October 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares	600	800
Stock purchased under share buyback, average price per share (in dollars per share)	$ 167.32	$ 170.87
Purchase Price	$ 100,000,000	$ 136,600,000