Reportable Segments - Results (Details) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2018	Oct. 31, 2017
Information as to operating segments
Net sales	$ 225,589	$ 212,766
Segment operating income	27,678	31,634
General corporate expenses	36,535	32,096
Operating Segment
Information as to operating segments
Segment operating income	38,851	40,833
Medical
Information as to operating segments
Net sales	127,552	112,385
Medical \| Operating Segment
Information as to operating segments
Segment operating income	25,211	19,684
Life Sciences
Information as to operating segments
Net sales	53,345	54,770
Life Sciences \| Operating Segment
Information as to operating segments
Segment operating income	6,331	10,375
Dental
Information as to operating segments
Net sales	36,628	37,677
Dental \| Operating Segment
Information as to operating segments
Segment operating income	5,925	8,675
Dialysis
Information as to operating segments
Net sales	8,064	7,934
Dialysis \| Operating Segment
Information as to operating segments
Segment operating income	1,384	2,099
General corporate \| Segment reconciling items
Information as to operating segments
General corporate expenses	$ 11,173	$ 9,199

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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