Income Tax - Income Before Income Taxes, Domestic and Foreign (Details) - USD ($) $ in Thousands	12 Months Ended
May. 31, 2015	May. 31, 2014	May. 31, 2013
Income Tax Disclosure [Abstract]
United States	$ 135,901	$ 153,453	$ 137,501
Foreign	281,209	223,897	196,783
Income before income taxes	$ 417,110	$ 377,350	$ 334,284

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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- References

No definition available.

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