Dividends Payable	3 Months Ended
Jul. 31, 2012
Dividends Payable [Abstract]
Dividends Payable	5. Dividends Payable On July 26, 2012, our Board of Directors approved a regular quarterly cash dividend of $0.233 per share on Class A and Class B Common Stock. The dividend will be paid on October 1, 2012 to stockholders of record as of September 7, 2012.

Tabular disclosure of all or some of the information related to dividends declared, but not paid, as of the financial reporting date.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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