Acquisitions (Details) $ in Thousands	12 Months Ended
Jul. 31, 2018 USD ($) business	Jul. 31, 2017 USD ($) business	Jul. 31, 2016 USD ($) business
Business Acquisition [Line Items]
Number of Businesses Acquired \| business	1	2	0
Total cash paid, net of cash acquired	$ 8,787	$ 160,812	$ 0
Acquisitions 2017 [Domain]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
Total acquisition price		$ 160,700
Allocation of the acquisition:
Accounts receivable and prepaid expenses		6,583
Vehicle pooling costs		571
Property and equipment		10,903
Inventory		1,067
Intangible assets		72,100
Goodwill		77,990
Liabilities assumed		(8,025)
Noncontrolling interest		(500)
Fair value of net assets and liabilities acquired		$ 160,689

Vehicle Pooling Costs, Business Combination

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Fair value portion of asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The number of businesses acquired by the entity during the period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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