Earnings Per Share - Buyback Activity by Program (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended	28 Months Ended
Nov. 30, 2018	Nov. 30, 2018	Nov. 30, 2018
Share Repurchase Programs
Equity, Class of Treasury Stock [Line Items]
Shares	1,941	2,331
Avg. Price per Share (in dollars per share)	$ 189.69	$ 191.58
Purchase Price	$ 368,126	$ 446,582
August 2, 2016
Equity, Class of Treasury Stock [Line Items]
Shares	1,740	2,130	2,600
Avg. Price per Share (in dollars per share)	$ 190.66	$ 192.55	$ 188.82
Purchase Price	$ 331,547	$ 410,003	$ 500,000
October 30, 2018
Equity, Class of Treasury Stock [Line Items]
Shares	201	201
Avg. Price per Share (in dollars per share)	$ 181.41	$ 181.41
Purchase Price	$ 36,579	$ 36,579

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