Intangibles and Goodwill - Goodwill Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018
Changes in Goodwill
Balance at the beginning of the period	$ 368,027	$ 311,445
Acquisitions	17,477	58,026
Divestitures	(491)
Foreign currency translation	(6,904)	(1,444)
Balance at the end of the period	378,109	368,027
Medical
Changes in Goodwill
Balance at the beginning of the period	186,690	129,945
Acquisitions	0	58,026
Divestitures	0
Foreign currency translation	(6,493)	(1,281)
Balance at the end of the period	180,197	186,690
Life Sciences
Changes in Goodwill
Balance at the beginning of the period	58,925	59,088
Acquisitions	6,137	0
Divestitures	(491)
Foreign currency translation	(90)	(163)
Balance at the end of the period	64,481	58,925
Dental
Changes in Goodwill
Balance at the beginning of the period	114,279	114,279
Acquisitions	11,340	0
Divestitures	0
Foreign currency translation	(321)	0
Balance at the end of the period	125,298	114,279
Dialysis
Changes in Goodwill
Balance at the beginning of the period	8,133	8,133
Acquisitions	0	0
Divestitures	0
Foreign currency translation	0	0
Balance at the end of the period	$ 8,133	$ 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.

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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.

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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.

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

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

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