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Intangible Assets and Goodwill - Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended
	Apr. 30, 2020	Apr. 30, 2019	Jul. 31, 2019	Jul. 31, 2018
Goodwill [Line Items]
Goodwill	$ 1,396,401	$ 1,350,187	$ 1,358,032	$ 377,693
Goodwill acquired	62,366	994,427
Measurement period adjustments	1,282
Foreign currency translation	(24,243)
Impairment charge	(1,036)
Activity		(21,933)
Other
Goodwill [Line Items]
Goodwill	105,237	42,871	42,871	42,871
Goodwill acquired	62,366	0
Measurement period adjustments	0
Foreign currency translation	0
Impairment charge	0
Activity		0
Europe \| Recreational vehicles
Goodwill [Line Items]
Goodwill	957,378	972,494	980,339	0
Goodwill acquired	0	994,427
Measurement period adjustments	1,282
Foreign currency translation	(24,243)
Impairment charge	0
Activity		(21,933)
Towables \| North America \| Recreational vehicles
Goodwill [Line Items]
Goodwill	333,786	334,822	334,822	334,822
Goodwill acquired	0	0
Measurement period adjustments	0
Foreign currency translation	0
Impairment charge	(1,036)
Activity		0
Motorized \| North America \| Recreational vehicles
Goodwill [Line Items]
Goodwill	0	0	$ 0	$ 0
Goodwill acquired	0	0
Measurement period adjustments	0
Foreign currency translation	0
Impairment charge	$ 0
Activity		$ 0