Income Taxes (Components of Income Before Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
May 31, 2014	May 31, 2013	May 31, 2012
Income before income taxes consist of the following components:
U.S. operations	$ 595,221	$ 485,046	$ 454,811
Foreign operations	12,637	14,862	16,133
Income before income taxes	$ 607,858	$ 499,908	$ 470,944

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.

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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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