Acquisitions Proforma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Jan. 31, 2018	Jan. 31, 2017
Business Combinations [Abstract]
Total revenues	$ 6,327,811	$ 5,705,758
Net earnings	$ 298,471	$ 148,834
Earnings per common share:
Pro forma earnings per share, basic (in dollars per share)	$ 7.83	$ 3.80
Pro forma earnings per share, diluted (in dollars per share)	$ 7.75	$ 3.75

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=79982066&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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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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