Intangible Assets, Net and Goodwill - Goodwill Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019
Changes in Goodwill
Balance at the beginning of the period	$ 378,109	$ 368,027
Acquisitions	275,944	17,477
Dispositions		(491)
Foreign currency translation	6,119	(6,904)
Balance at the end of the period	660,172	378,109
Medical
Changes in Goodwill
Balance at the beginning of the period	180,197	186,690
Acquisitions	0	0
Dispositions		0
Foreign currency translation	5,725	(6,493)
Balance at the end of the period	185,922	180,197
Life Sciences
Changes in Goodwill
Balance at the beginning of the period	64,481	58,925
Acquisitions	0	6,137
Dispositions		(491)
Foreign currency translation	(87)	(90)
Balance at the end of the period	64,394	64,481
Dental
Changes in Goodwill
Balance at the beginning of the period	125,298	114,279
Acquisitions	275,944	11,340
Dispositions		0
Foreign currency translation	481	(321)
Balance at the end of the period	401,723	125,298
Dialysis
Changes in Goodwill
Balance at the beginning of the period	8,133	8,133
Acquisitions	0	0
Dispositions		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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