Acquisition - Erwin Hymer Group - Pro Forma Information (Detail) $ / shares in Units, $ in Thousands	3 Months Ended
Oct. 31, 2018 USD ($) $ / shares
Business Combinations [Abstract]
Net sales \| $	$ 2,327,268
Net income \| $	$ 22,461
Basic earnings per common share (in dollars per share) \| $ / shares	$ 0.41
Diluted earnings per common share (in dollars per share) \| $ / shares	$ 0.41

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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Section 50
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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