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 (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Finite-Lived Intangible Assets
Amortization expense	$ 2.4	$ 2.1	$ 4.5	$ 4.2
Customer Relationships
Finite-Lived Intangible Assets
Amortization expense			3.2
Solaris
Finite-Lived Intangible Assets
Finite lived intangible assets acquired in business combination	20.8		20.8
Solaris \| Technology
Finite-Lived Intangible Assets
Finite lived intangible assets acquired in business combination	17.3		$ 17.3
Useful life			15 years
Solaris \| Trademarks and Trade Names
Finite-Lived Intangible Assets
Finite lived intangible assets acquired in business combination	3.3		$ 3.3
Useful life			10 years
Solaris \| Backlog
Finite-Lived Intangible Assets
Finite lived intangible assets acquired in business combination	0.2		$ 0.2
Useful life			6 months
PAIS
Finite-Lived Intangible Assets
Finite lived intangible assets acquired in business combination	3.0		$ 3.0
Useful life			20 years
PAIS \| Customer Relationships
Finite-Lived Intangible Assets
Finite lived intangible assets acquired in business combination	$ 3.0		$ 3.0