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, 2021	Apr. 30, 2020	Apr. 30, 2021	Apr. 30, 2020	Jul. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Effect of foreign currency exchange rates			$ 3,893
Amortization of Intangible Assets	$ 1,800	$ 2,200	5,300	$ 7,000
Amortized intangibles:
Accumulated amortization	(39,365)		(39,365)		$ (34,093)
Net intangibles	42,535		42,535		47,772
Supply contracts and customer relationships
Amortized intangibles:
Gross carrying amount	50,573		50,573		50,600
Trade names
Amortized intangibles:
Gross carrying amount	23,682		23,682		23,635
Licenses and databases
Amortized intangibles:
Gross carrying amount	$ 7,645		$ 7,645		$ 7,630