Reportable Segments - Results (Details) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2019	Oct. 31, 2018
Information as to operating segments
Net sales	$ 257,246	$ 225,589
Segment operating income	14,424	27,678
General corporate expenses	55,287	36,535
Operating Segment
Information as to operating segments
Segment operating income	34,880	38,851
Segment reconciling items
Information as to operating segments
General corporate expenses	20,456	11,173
Medical
Information as to operating segments
Net sales	133,353	127,552
Medical \| Operating Segment
Information as to operating segments
Segment operating income	21,119	25,211
Life Sciences
Information as to operating segments
Net sales	49,141	51,842
Life Sciences \| Operating Segment
Information as to operating segments
Segment operating income	7,135	5,572
Dental
Information as to operating segments
Net sales	67,243	38,131
Dental \| Operating Segment
Information as to operating segments
Segment operating income	5,004	6,684
Dialysis
Information as to operating segments
Net sales	7,509	8,064
Dialysis \| Operating Segment
Information as to operating segments
Segment operating income	$ 1,622	$ 1,384

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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