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Intangible Assets and Goodwill - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Goodwill [Line Items]
Goodwill	$ 1,481,283	$ 1,361,265	$ 1,476,541	$ 1,358,032
Goodwill acquired	17,882
Measurement period adjustments		3,054
Foreign currency translation	(13,140)	179
Other
Goodwill [Line Items]
Goodwill	122,708	42,871	104,826	42,871
Goodwill acquired	17,882
Measurement period adjustments		0
Foreign currency translation	0	0
Europe \| Recreational vehicles
Goodwill [Line Items]
Goodwill	1,024,789	983,572	1,037,929	980,339
Goodwill acquired	0
Measurement period adjustments		3,054
Foreign currency translation	(13,140)	179
North American Towables \| North America \| Recreational vehicles
Goodwill [Line Items]
Goodwill	333,786	334,822	333,786	334,822
Goodwill acquired	0
Measurement period adjustments		0
Foreign currency translation	0	0
North American Motorized \| North America \| Recreational vehicles
Goodwill [Line Items]
Goodwill	0	0	$ 0	$ 0
Goodwill acquired	0
Measurement period adjustments		0
Foreign currency translation	$ 0	$ 0