Intangibles and Goodwill - Goodwill Rollforward (Details) $ in Thousands	3 Months Ended
Oct. 31, 2017 USD ($)
Changes in Goodwill
Balance at the beginning of the period	$ 311,445
Acquisitions	41,509
Foreign currency translation	(1,136)
Balance at the end of the period	351,818
Endoscopy
Changes in Goodwill
Balance at the beginning of the period	129,945
Acquisitions	41,509
Foreign currency translation	(968)
Balance at the end of the period	170,486
Water Purification and Filtration
Changes in Goodwill
Balance at the beginning of the period	59,088
Acquisitions	0
Foreign currency translation	(168)
Balance at the end of the period	58,920
Healthcare Disposables
Changes in Goodwill
Balance at the beginning of the period	114,279
Acquisitions	0
Foreign currency translation	0
Balance at the end of the period	114,279
Dialysis
Changes in Goodwill
Balance at the beginning of the period	8,133
Acquisitions	0
Foreign currency translation	0
Balance at the end of the period	$ 8,133

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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