Revenue Recognition (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 2,003,133	$ 1,290,576	$ 4,161,918	$ 3,046,552
Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	1,964,702	1,253,059
Operating Segments | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	1,964,702	1,253,059	4,074,486	2,963,355
Operating Segments | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	1,327,587	1,253,059	2,944,364	2,963,355
Operating Segments | Europe | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	637,115	0	1,130,122	0
Operating Segments | Travel Trailers And Other Towables | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	583,121	535,779	1,292,786	1,297,263
Operating Segments | Fifth Wheels Towables | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	400,786	345,785	892,009	863,399
Operating Segments | Towables | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	983,907	881,564	2,184,795	2,160,662
Operating Segments | Class A Motorized | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	125,474	173,488	287,206	400,762
Operating Segments | Class C Motorized | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	186,761	182,502	416,598	366,886
Operating Segments | Class B Motorized | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	31,445	15,505	55,765	35,045
Operating Segments | Motorized | North America | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	343,680	371,495	759,569	802,693
Operating Segments | Motorcaravan | Europe | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	382,422	0	664,155	0
Operating Segments | Campervan | Europe | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	97,923	0	175,520	0
Operating Segments | Caravan | Europe | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	69,909	0	130,941	0
Operating Segments | Other RV Related | Europe | Recreational vehicles
Disaggregation of Revenue [Line Items]
Net sales	86,861	0	159,506	0
Corporate and Eliminations
Disaggregation of Revenue [Line Items]
Net sales	57,745	55,114	131,311	128,962
Intercompany eliminations
Disaggregation of Revenue [Line Items]
Net sales	$ (19,314)	$ (17,597)	$ (43,879)	$ (45,765)