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Intangible Assets and Goodwill - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Goodwill [Line Items]
Goodwill	$ 1,361,265	$ 377,693	$ 1,358,032	$ 377,693
Measurement period adjustments	3,054
Foreign currency translation	179
Activity		0
Other
Goodwill [Line Items]
Goodwill	42,871	42,871	42,871	42,871
Measurement period adjustments	0
Foreign currency translation	0
Activity		0
Europe \| Recreational vehicles
Goodwill [Line Items]
Goodwill	983,572	0	980,339	0
Measurement period adjustments	3,054
Foreign currency translation	179
Activity		0
Towables \| North America \| Recreational vehicles
Goodwill [Line Items]
Goodwill	334,822	334,822	334,822	334,822
Measurement period adjustments	0
Foreign currency translation	0
Activity		0
Motorized \| North America \| Recreational vehicles
Goodwill [Line Items]
Goodwill	0	0	$ 0	$ 0
Measurement period adjustments	0
Foreign currency translation	$ 0
Activity		$ 0