Schedule of Segment Reporting Information by Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016
Segment Reporting Information [Line Items]
Net sales	$ 2,015,224	$ 1,284,054	$ 5,312,280	$ 3,289,476
Income (loss) from continuing operations before income taxes	166,231	116,283	380,396	259,862
Operating Segments | Recreational vehicles
Segment Reporting Information [Line Items]
Income (loss) from continuing operations before income taxes	171,860	121,008	401,444	279,473
Operating Segments | Recreational vehicles | Towables
Segment Reporting Information [Line Items]
Income (loss) from continuing operations before income taxes	134,504	96,893	306,677	213,186
Operating Segments | Recreational vehicles | Motorized
Segment Reporting Information [Line Items]
Income (loss) from continuing operations before income taxes	37,356	24,115	94,767	66,287
Operating Segments | Other
Segment Reporting Information [Line Items]
Income (loss) from continuing operations before income taxes	8,713	6,441	20,787	12,107
Operating Segments | Corporate
Segment Reporting Information [Line Items]
Income (loss) from continuing operations before income taxes	(14,342)	(11,166)	(41,835)	(31,718)
Continuing Operations
Segment Reporting Information [Line Items]
Net sales	2,015,224	1,284,054	5,312,280	3,289,476
Continuing Operations | Operating Segments | Recreational vehicles
Segment Reporting Information [Line Items]
Net sales	1,976,075	1,242,204	5,205,623	3,179,167
Continuing Operations | Operating Segments | Recreational vehicles | Towables
Segment Reporting Information [Line Items]
Net sales	1,426,192	934,574	3,719,314	2,377,571
Continuing Operations | Operating Segments | Recreational vehicles | Motorized
Segment Reporting Information [Line Items]
Net sales	549,883	307,630	1,486,309	801,596
Continuing Operations | Operating Segments | Other
Segment Reporting Information [Line Items]
Net sales	70,019	61,572	182,906	159,965
Continuing Operations | Intercompany Eliminations
Segment Reporting Information [Line Items]
Net sales	$ (30,870)	$ (19,722)	$ (76,249)	$ (49,656)