Acquisitions - Additional Information (Detail) - USD ($) $ in Thousands								3 Months Ended		12 Months Ended
	May. 01, 2015	Jan. 05, 2015	May. 01, 2014	Oct. 31, 2013	Aug. 30, 2013	Dec. 20, 2012	Oct. 03, 2012	Jul. 31, 2015	Apr. 30, 2014	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Business Acquisition [Line Items]
Payment to acquire business, net										$ 194,486	$ 86,092	$ 10,718
Business acquisition allocated to goodwill								$ 312,622		312,622	$ 256,579	$ 238,103
K.Z. Inc.
Business Acquisition [Line Items]
Payment to acquire business			$ 53,405
Asset purchase agreement date			May 01, 2014
Amortizable intangible assets, weighted average useful life			13 years 10 months 24 days
Purchase price adjustment			$ 2,915
Cash on hand at the acquisition date			996
Payment to acquire business, net			55,324
Business acquisition allocated to property and equipment			15,057
Business acquisition allocated to goodwill			$ 2,703
Bison
Business Acquisition [Line Items]
Payment to acquire business				$ 16,718					$ 16,914
Asset purchase agreement date				Oct. 31, 2013
Amortizable intangible assets, weighted average useful life				13 years 3 months 18 days
Additional cash payment									$ 196
Business acquisition allocated to property and equipment				$ 625
Business acquisition allocated to goodwill				$ 6,660
Livin' Lite
Business Acquisition [Line Items]
Asset purchase agreement date					Aug. 30, 2013
Amortizable intangible assets, weighted average useful life					10 years 2 months 12 days
Cash on hand at the acquisition date					$ 247
Payment to acquire business, net					16,769
Business acquisition allocated to property and equipment					137
Business acquisition allocated to goodwill					$ 9,113
Cruiser RV, LLC and DRV, LLC
Business Acquisition [Line Items]
Payment to acquire business		$ 47,412
Asset purchase agreement date		Dec. 31, 2014
Amortizable intangible assets, weighted average useful life		13 years 10 months 24 days
Purchase price adjustment								1,173
Cash on hand at the acquisition date		$ 1,062						1,062		$ 1,062
Payment to acquire business, net		47,523						$ 47,523
Business acquisition allocated to property and equipment		4,533
Business acquisition allocated to goodwill		$ 13,172
Postle Operating, LLC
Business Acquisition [Line Items]
Payment to acquire business	$ 144,048
Asset purchase agreement date										May 01, 2015
Amortizable intangible assets, weighted average useful life	12 years 3 months 18 days
Cash on hand at the acquisition date	$ 2,963
Payment to acquire business, net	144,048
Business acquisition allocated to property and equipment	32,251
Business acquisition allocated to goodwill	$ 42,871
Buses
Business Acquisition [Line Items]
Payment to acquire business						$ 6,804	$ 3,914
Asset purchase agreement date							Oct. 03, 2012
Business acquisition allocated to inventory						804	$ 915
Business acquisition allocated to property and equipment						630	331
Business acquisition allocated to Certain liabilities						225
Business acquisition allocated to goodwill						4,495	768
Dealer Networks
Business Acquisition [Line Items]
Intangible assets amortization period		12 years	12 years	12 years	8 years
Amortizable intangible assets, amortization method										Accelerated cash flow basis
Dealer Networks | K.Z. Inc.
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset			$ 13,160
Dealer Networks | Bison
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset				$ 7,400
Dealer Networks | Livin' Lite
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset					$ 3,200
Dealer Networks | Cruiser RV, LLC and DRV, LLC
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset		$ 14,300
Dealer Networks | Buses
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset						410	900
Trademarks
Business Acquisition [Line Items]
Intangible assets amortization period	15 years	20 years	20 years	20 years	20 years					19 years
Amortizable intangible assets, amortization method										Straight-line basis
Trademarks | K.Z. Inc.
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset			$ 5,540
Trademarks | Bison
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset				$ 1,800
Trademarks | Livin' Lite
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset					$ 1,500
Trademarks | Cruiser RV, LLC and DRV, LLC
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset		$ 5,400
Trademarks | Postle Operating, LLC
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset	$ 6,000
Trademarks | Buses
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset						670	$ 1,000
Non-Compete Agreements
Business Acquisition [Line Items]
Intangible assets amortization period			5 years		2 years					3 years
Amortizable intangible assets, amortization method										Straight-line basis
Non-Compete Agreements | K.Z. Inc.
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset			$ 450
Non-Compete Agreements | Livin' Lite
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset					$ 130
Backlog
Business Acquisition [Line Items]
Intangible assets amortization period	42 days	42 days	2 months	42 days	42 days
Amortizable intangible assets, amortization method										Straight-line basis
Backlog | K.Z. Inc.
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset			$ 420
Backlog | Bison
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset				$ 140
Backlog | Livin' Lite
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset					$ 110
Backlog | Cruiser RV, LLC and DRV, LLC
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset		$ 450
Backlog | Postle Operating, LLC
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset	$ 300
Backlog | Buses
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset						$ 20
Design Technology Assets
Business Acquisition [Line Items]
Intangible assets amortization period					5 years
Amortizable intangible assets, amortization method										Straight-line basis
Design Technology Assets | Livin' Lite
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset					$ 1,100
Customer Relationships
Business Acquisition [Line Items]
Intangible assets amortization period	12 years
Amortizable intangible assets, amortization method										Accelerated cash flow basis
Customer Relationships | Postle Operating, LLC
Business Acquisition [Line Items]
Business acquisition allocated to amortizing intangible asset	$ 38,800