Stock Option Activity (Detail) shares in Thousands	3 Months Ended
Aug. 31, 2018 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Shares Outstanding, Beginning Balance \| shares	2,497,124
Shares, Granted \| shares	0
Shares, Exercised \| shares	(253,076)
Shares, Forfeited \| shares	(8,210)
Shares Outstanding, Ending Balance \| shares	2,235,838
Weighted-Average Exercise Price, Beginning Balance \| $ / shares	$ 42.63
Weighted-Average Exercise Price, Granted \| $ / shares	0
Weighted-Average Exercise Price, Exercised \| $ / shares	28.60
Weighted-Average Exercise Price, Forfeited \| $ / shares	44.51
Weighted-Average Exercise Price, Ending Balance \| $ / shares	$ 44.21

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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