Income Taxes - Components of Income Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
May. 31, 2015	May. 31, 2014	May. 31, 2013
Income before income taxes for continuing operations consists of the following components:
U.S. operations	$ 630,740	$ 594,840	$ 482,679
Foreign operations	18,733	12,202	17,996
Income before income taxes from continuing operations	$ 649,473	$ 607,042	$ 500,675

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

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 20

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=51673353&loc=d3e41242-110953

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

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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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- References

No definition available.

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