Business Segments - Schedule of Reporting Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019	Jul. 31, 2019
Segment Reporting Information [Line Items]
Net sales	$ 1,681,735	$ 2,506,583	$ 5,843,653	$ 5,553,135
Income (loss) from continuing operations before income taxes	21,229	41,523	124,726	74,913
Total assets	5,612,290		5,612,290		$ 5,660,446
Depreciation and amortization expense, total	45,459	50,930	144,611	97,510
Capital acquisitions	23,870	32,647	75,027	82,564
Recreational vehicles
Segment Reporting Information [Line Items]
Net sales	1,652,771	2,464,002
Operating Segments | Recreational vehicles
Segment Reporting Information [Line Items]
Net sales	1,652,771	2,464,002	5,727,257	5,427,357
Income (loss) from continuing operations before income taxes	59,934	97,953	236,039	245,480
Total assets	4,772,193		4,772,193		5,040,949
Depreciation and amortization expense, total	42,345	47,818	135,558	88,299
Capital acquisitions	23,232	31,980	72,533	78,705
Operating Segments | Recreational vehicles | North American
Segment Reporting Information [Line Items]
Net sales	1,037,428	1,696,493	3,981,792	4,659,848
Income (loss) from continuing operations before income taxes	60,176	128,900	254,615	276,427
Total assets	1,709,306		1,709,306		1,963,145
Depreciation and amortization expense, total	20,296	20,591	60,006	61,072
Capital acquisitions	7,352	16,101	34,476	62,826
Operating Segments | Recreational vehicles | North American | Towables
Segment Reporting Information [Line Items]
Net sales	773,391	1,237,255	2,958,186	3,397,917
Income (loss) from continuing operations before income taxes	49,261	103,715	207,009	212,325
Total assets	1,309,649		1,309,649		1,516,519
Depreciation and amortization expense, total	16,696	17,097	49,398	50,699
Capital acquisitions	5,192	13,013	23,888	49,510
Operating Segments | Recreational vehicles | North American | Motorized
Segment Reporting Information [Line Items]
Net sales	264,037	459,238	1,023,606	1,261,931
Income (loss) from continuing operations before income taxes	10,915	25,185	47,606	64,102
Total assets	399,657		399,657		446,626
Depreciation and amortization expense, total	3,600	3,494	10,608	10,373
Capital acquisitions	2,160	3,088	10,588	13,316
Operating Segments | Recreational vehicles | European
Segment Reporting Information [Line Items]
Net sales	615,343	767,509	1,745,465	767,509
Income (loss) from continuing operations before income taxes	(242)	(30,947)	(18,576)	(30,947)
Total assets	3,062,887		3,062,887		3,077,804
Depreciation and amortization expense, total	22,049	27,227	75,552	27,227
Capital acquisitions	15,880	15,879	38,057	15,879
Other, net
Segment Reporting Information [Line Items]
Net sales	45,632	69,506	176,943	198,468
Income (loss) from continuing operations before income taxes	3,996	7,868	24,356	19,728
Total assets	222,874		222,874		163,897
Depreciation and amortization expense, total	2,676	2,705	7,710	7,972
Capital acquisitions	517	248	1,445	2,979
Corporate
Segment Reporting Information [Line Items]
Income (loss) from continuing operations before income taxes	(42,701)	(64,298)	(135,669)	(190,295)
Total assets	617,223		617,223		$ 455,600
Depreciation and amortization expense, total	438	407	1,343	1,239
Capital acquisitions	121	419	1,049	880
Intercompany eliminations
Segment Reporting Information [Line Items]
Net sales	$ (16,668)	$ (26,925)	$ (60,547)	$ (72,690)