The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019	Jul. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Goodwill, acquired during period			$ 3,672
Effect of foreign currency exchange rates			1,046
Amortization of Intangible Assets	$ 2,200	$ 2,500	7,000	$ 8,000
Amortized intangibles:
Accumulated amortization	(32,078)		(32,078)		$ (25,142)
Net intangibles	48,671		48,671		55,156
Supply contracts and customer relationships
Amortized intangibles:
Gross carrying amount	49,455		49,455		49,109
Trade names
Amortized intangibles:
Gross carrying amount	23,477		23,477		23,501
Licenses and databases
Amortized intangibles:
Gross carrying amount	$ 7,817		$ 7,817		$ 7,688