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		6 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020	Jul. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Effect of foreign currency exchange rates			$ 3,344
Amortization of Intangible Assets	$ 1,700	$ 2,300	3,500	$ 4,800
Amortized intangibles:
Accumulated amortization	(37,662)		(37,662)		$ (34,093)
Net intangibles	44,270		44,270		47,772
Supply contracts and customer relationships
Amortized intangibles:
Gross carrying amount	50,580		50,580		50,600
Trade names
Amortized intangibles:
Gross carrying amount	23,700		23,700		23,635
Licenses and databases
Amortized intangibles:
Gross carrying amount	$ 7,652		$ 7,652		$ 7,630