Schedule of Segment Reporting Information, by Segment Balance Sheet Item (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017	Jul. 31, 2017
Segment Reporting Information [Line Items]
Total assets	$ 2,866,482		$ 2,866,482		$ 2,557,931
Depreciation and amortization expense, total	23,533	$ 23,893	69,506	$ 74,298
Capital acquisitions	34,171	28,233	95,837	78,523
Operating Segments | Recreational vehicles
Segment Reporting Information [Line Items]
Total assets	2,372,676		2,372,676		2,035,790
Depreciation and amortization expense, total	20,361	20,529	60,014	64,282
Capital acquisitions	33,258	27,693	83,740	76,056
Operating Segments | Recreational vehicles | Towables
Segment Reporting Information [Line Items]
Total assets	1,754,486		1,754,486		1,535,029
Depreciation and amortization expense, total	17,357	18,213	51,373	57,377
Capital acquisitions	23,175	15,559	59,588	51,877
Operating Segments | Recreational vehicles | Motorized
Segment Reporting Information [Line Items]
Total assets	618,190		618,190		500,761
Depreciation and amortization expense, total	3,004	2,316	8,641	6,905
Capital acquisitions	10,083	12,134	24,152	24,179
Corporate and Eliminations [Member]
Segment Reporting Information [Line Items]
Total assets	158,914		158,914		156,996
Depreciation and amortization expense, total	2,762	3,021	8,319	9,037
Capital acquisitions	744	163	3,337	773
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Total assets	334,892		334,892		$ 365,145
Depreciation and amortization expense, total	410	343	1,173	979
Capital acquisitions	$ 169	$ 377	$ 8,760	$ 1,694