Intangible Assets and Goodwill - Components of Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	Oct. 31, 2020	Jul. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Cost	$ 1,252,581	$ 1,255,441
Accumulated amortization	367,127	340,717
Dealer networks/customer relationships
Finite-Lived Intangible Assets [Line Items]
Cost	763,378	766,198
Accumulated amortization	270,510	252,320
Trademarks
Finite-Lived Intangible Assets [Line Items]
Cost	276,985	275,775
Accumulated amortization	51,066	47,743
Design technology and other intangibles
Finite-Lived Intangible Assets [Line Items]
Cost	212,218	213,468
Accumulated amortization	$ 45,551	$ 40,654