Revenue Recognition - Schedule of Disaggregates of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018
Disaggregation of Revenue [Line Items]
Net sales	$ 1,290,576	$ 1,971,560	$ 3,046,552	$ 4,203,228
Operating Segments | Travel Trailers And Other Towables
Disaggregation of Revenue [Line Items]
Net sales	535,779	829,318	1,297,263	1,822,922
Operating Segments | Fifth Wheels Towables
Disaggregation of Revenue [Line Items]
Net sales	345,785	543,800	863,399	1,168,697
Operating Segments | Towables
Disaggregation of Revenue [Line Items]
Net sales	881,564	1,373,118	2,160,662	2,991,619
Operating Segments | Class A Motorized
Disaggregation of Revenue [Line Items]
Net sales	173,488	257,092	400,762	509,515
Operating Segments | Class C Motorized
Disaggregation of Revenue [Line Items]
Net sales	182,502	278,853	366,886	565,519
Operating Segments | Class B Motorized
Disaggregation of Revenue [Line Items]
Net sales	15,505	23,964	35,045	51,486
Operating Segments | Motorized
Disaggregation of Revenue [Line Items]
Net sales	371,495	559,909	802,693	1,126,520
Corporate and Eliminations
Disaggregation of Revenue [Line Items]
Net sales	55,114	68,013	128,962	150,932
Intercompany Eliminations
Disaggregation of Revenue [Line Items]
Net sales	$ (17,597)	$ (29,480)	$ (45,765)	$ (65,843)