Earnings per Share - Summary of Buyback Activity by Program (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	21 Months Ended
Aug. 31, 2021	Aug. 31, 2020	Jul. 31, 2021
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback	$ 659,235	$ 69,011
Share Buyback Programs
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback (shares)	1,590	0
Stock purchased under share buyback, average price (in dollars per share)	$ 365.41	$ 0
Stock purchased under share buyback	$ 581,220	$ 0
October 29, 2019 Plan
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback (shares)	1,590	0	2,800
Stock purchased under share buyback, average price (in dollars per share)	$ 365.41	$ 0	$ 358.93
Stock purchased under share buyback	$ 581,220	$ 0	$ 1,000,000
July 27, 2021 Plan
Equity, Class of Treasury Stock [Line Items]
Stock purchased under share buyback (shares)	0	0
Stock purchased under share buyback, average price (in dollars per share)	$ 0	$ 0
Stock purchased under share buyback	$ 0	$ 0

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