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Earnings Per Share - Narrative (Details) - USD ($)	1 Months Ended	3 Months Ended						9 Months Ended		17 Months Ended
Earnings Per Share - Narrative (Details) - USD ($)	Mar. 31, 2020	Feb. 29, 2020	Nov. 30, 2019	Aug. 31, 2019	Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	Feb. 29, 2020	Feb. 28, 2019	Mar. 31, 2020	Oct. 29, 2019	Oct. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Basic earnings from discontinued operations (in dollars per share)		$ 0.00			$ 0.02			$ 0	$ 0.02
Diluted earnings from discontinued operations (in dollars per share)		$ 0.00			$ 0.02			$ 0.00	$ 0.02
Options granted and excluded from the computation of diluted earnings per share (in shares)		200,000			700,000			200,000	500,000
Stock purchased under share buyback		$ 2,586,000	$ 1,911,000	$ 256,830,000	$ 100,095,000	$ 368,661,000	$ 139,468,000
Employee Payroll Taxes Due on Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock purchased under share buyback (shares)		100,000						300,000
Stock purchased under share buyback, average price per share (in dollars per share)		$ 278.21						$ 261.48
Stock purchased under share buyback		$ 2,500,000						$ 68,400,000
October 30, 2018 Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share buyback program, authorized amount												$ 1,000,000,000.0
Stock purchased under share buyback (shares)		0						800,000
Stock purchased under share buyback, average price per share (in dollars per share)								$ 230.66
Stock purchased under share buyback								$ 193,100,000
October 29, 2019 Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share buyback program, authorized amount											$ 1,000,000,000.0
Stock purchased under share buyback (shares)		0						0
Subsequent Event \| October 30, 2018 Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock purchased under share buyback (shares)	800,000									4,300,000
Stock purchased under share buyback, average price per share (in dollars per share)	$ 263.07									$ 219.40
Stock purchased under share buyback	$ 202,600,000									$ 939,100,000