Summary of Option and Share-Based Payment Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands	12 Months Ended
May 31, 2023	May 31, 2022	May 31, 2021
Stock Options And Stock Appreciation Rights
Weighted Average Exercise Price
Beginning balance	$ 63.16
Options granted	81.01
Options exercised	49.52
Ending balance	68.19	$ 63.16
Exercisable at May 31, 2023	$ 61.09
Number of Shares Under Option
Beginning balance	2,300
Options granted	360
Options exercised	(372)
Ending balance	2,288	2,300
Exercisable at May 31, 2023	1,448
SARs
Number of Shares Under Option
Weighted-average grant-date fair value per SAR	$ 18.09	$ 16.72	$ 14.38
Fair value of SARS vested	$ 14,190	$ 13,490	$ 12,590
Intrinsic value of options exercised	11,260	13,770	8,800
Tax benefit from options exercised	$ 3,292,000	$ 88,000	$ 8,821,000

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=SL79508275-113901

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Net number of share options (or share units) granted during the period.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
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