Summary of Components of Net Balance (Detail) - USD ($) $ in Thousands	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Goodwill [Line Items]
Goodwill, gross	$ 329,874		$ 255,355
Accumulated impairment charges	(17,252)		(17,252)
Goodwill	312,622	$ 256,579	238,103
Towables
Goodwill [Line Items]
Goodwill, gross	269,751		238,103
Goodwill	269,751	$ 256,579	238,103
Motorized
Goodwill [Line Items]
Goodwill, gross	17,252		17,252
Accumulated impairment charges	(17,252)		$ (17,252)
Other
Goodwill [Line Items]
Goodwill, gross	42,871
Goodwill	$ 42,871

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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