Summary of Option and Share-Based Payment Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands	12 Months Ended
May 31, 2021	May 31, 2020	May 31, 2019
Stock Options And Stock Appreciation Rights
Weighted Average Exercise Price
Beginning balance	$ 49.88
Options granted	78.49
Options exercised	39.69
Ending balance	59.28	$ 49.88
Exercisable at May 31, 2021	$ 52.56
Number of Shares Under Option
Beginning balance	2,482
Options granted	360
Options exercised	(837)
Ending balance	2,005	2,482
Exercisable at May 31, 2021	1,107
SARs
Number of Shares Under Option
Weighted-average grant-date fair value per SAR	$ 14.38	$ 11.59	$ 14.08
Intrinsic value of options exercised	$ 8,800	$ 9,620	$ 9,290
Tax benefit from options exercised	8,821,000	5,936,000	3,210,000
Fair value of SARS vested	$ 12,590	$ 12,270	$ 9,300

Amount of tax benefit from exercise of option under share-based payment arrangement.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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