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
-Subparagraph (a)
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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Summary of Components of Net Balance (Detail) - USD ($) $ in Thousands	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014
Goodwill [Line Items]
Goodwill, gross	$ 404,058
Accumulated impairment charges	(26,365)
Goodwill	377,693	$ 312,622	$ 256,579
Towables
Goodwill [Line Items]
Goodwill, gross	343,935
Accumulated impairment charges	(9,113)
Goodwill	334,822	269,751	$ 256,579
Motorized
Goodwill [Line Items]
Goodwill, gross	17,252
Accumulated impairment charges	(17,252)
Other
Goodwill [Line Items]
Goodwill, gross	42,871
Goodwill	$ 42,871	$ 42,871