Earnings per Share - Summary of Buyback Activity by Program (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
May 31, 2021	May 31, 2020	May 31, 2019
Equity, Class of Treasury Stock [Line Items]
Purchase Price	$ 554,121	$ 464,518	$ 1,016,300
Share Repurchase Programs
Equity, Class of Treasury Stock [Line Items]
Shares	1,386	1,607	4,803
Average Price per Share (in dollars per share)	$ 346.13	$ 246.19	$ 198.53
Purchase Price	$ 479,656	$ 395,681	$ 953,445
Buyback Program, August 2016
Equity, Class of Treasury Stock [Line Items]
Shares	0	0	2,130
Average Price per Share (in dollars per share)	$ 0	$ 0	$ 192.55
Purchase Price	$ 0	$ 0	$ 410,003
Buyback Program, October 2018
Equity, Class of Treasury Stock [Line Items]
Shares	190	1,607	2,673
Average Price per Share (in dollars per share)	$ 319.88	$ 246.19	$ 203.30
Purchase Price	$ 60,877	$ 395,681	$ 543,442
Buyback Program, October 2019
Equity, Class of Treasury Stock [Line Items]
Shares	1,196	0	0
Average Price per Share (in dollars per share)	$ 350.31	$ 0	$ 0
Purchase Price	$ 418,779	$ 0	$ 0

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Total cost of shares repurchased divided by the total number of shares repurchased.

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