Reportable Segments - Narrative (Details) - Customer concentration - Segment sales	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Two Customers \| Life Sciences
Segment Reporting Information [Line Items]
Concentration risk within segment (as a percent)	41.70%	40.20%	48.00%
Two Customers \| Dialysis
Segment Reporting Information [Line Items]
Concentration risk within segment (as a percent)	41.00%	41.00%	40.60%
Three Customers \| Dental
Segment Reporting Information [Line Items]
Concentration risk within segment (as a percent)	42.00%	47.60%	45.10%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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