Earnings per Share - Summary of Buyback Activity by Program (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback	$ 69,011	$ 256,830
Share Repurchase Programs
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback (shares)	0	837
Stock purchased under share buyback, average price per share (in dollars per share)	$ 0	$ 230.66
Stock purchased under share buyback	$ 0	$ 193,109
October 30, 2018 Plan
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback (shares)	0	837
Stock purchased under share buyback, average price per share (in dollars per share)	$ 0	$ 230.66
Stock purchased under share buyback	$ 0	$ 193,109
October 29, 2019 Plan
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback (shares)	0	0
Stock purchased under share buyback, average price per share (in dollars per share)	$ 0	$ 0
Stock purchased under share buyback	$ 0	$ 0

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