Acquisitions - Summary of Unaudited Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Apr. 30, 2015	Apr. 30, 2014
Business Combinations [Abstract]
Total revenue	$ 7,794,626	$ 7,948,786
Net income	$ 181,100	$ 128,265
Net income per common share
Basic (in Dollars per share)	$ 4.67	$ 3.34
Diluted (in Dollars per share)	$ 4.63	$ 3.30

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.

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=56956515&loc=d3e1392-128463

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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.

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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.

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