Note 3 - Acquisitions (Details) - Unaudited Pro Forma Information (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Apr. 30, 2014	Apr. 30, 2013
Unaudited Pro Forma Information [Abstract]
Total revenue	$ 7,885,634	$ 7,362,816
Net income	$ 127,615	$ 105,699
Net income per common share
Basic	$ 3.32	$ 2.76
Diluted	$ 3.28	$ 2.73

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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