SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail) $ in Thousands	12 Months Ended
	Jul. 31, 2021 USD ($)	Jul. 31, 2021 USD ($)	Jul. 31, 2021 USD ($) Segment	Jul. 31, 2021 USD ($)	Jul. 31, 2021 USD ($) shares	Jul. 31, 2021 USD ($) segment	Jul. 31, 2020 USD ($) shares	Jul. 31, 2019 USD ($) shares
Summary Of Significant Accounting Policies [Line Items]
Number of reportable segments			3			3
Cash and cash equivalents	$ 445,852	$ 445,852	$ 445,852	$ 445,852	$ 445,852	$ 445,852	$ 538,519	$ 425,615
Depreciation		113,398					98,933	73,139
Advertising costs		44,638					$ 67,019	$ 38,643
Maximum percentage of tax benefits realized upon ultimate settlement				50.00%
Stock-based compensation, requisite service period	3 years
Restricted Stock Units (RSUs) and Performance Stock Units (PSUs)
Summary Of Significant Accounting Policies [Line Items]
Antidilutive restricted stock units and unvested restricted stock outstanding (in shares) | shares					0		0	233,395
Research and Development Expense
Summary Of Significant Accounting Policies [Line Items]
Research and development expense		26,775					$ 19,123	$ 9,381
Continuing Operations | Selling, General and Administrative Expenses
Summary Of Significant Accounting Policies [Line Items]
Depreciation		22,409					15,060	$ 8,350
Backlog
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	9 months
Rental vehicles
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	6 years
Minimum | Non-compete agreements
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	2 years
Minimum | Trademarks
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	15 years
Minimum | Dealer network
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	12 years
Minimum | Building and Building Improvements
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	10 years
Minimum | Machinery and equipment
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	3 years
Maximum | Non-compete agreements
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	15 years
Maximum | Trademarks
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	25 years
Maximum | Dealer network
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life	20 years
Maximum | Building and Building Improvements
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	39 years
Maximum | Machinery and equipment
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	10 years
Euro Financial Institutions One
Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	$ 111,215	111,215	111,215	$ 111,215	$ 111,215	111,215	174,077
Euro Financial Institutions Two
Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	27,926	27,926	27,926	27,926	27,926	27,926	49,732
Held By One U.S. Financial Institution
Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	$ 260,101	$ 260,101	$ 260,101	$ 260,101	$ 260,101	$ 260,101	$ 260,876