Acquisitions (Details 4)		12 Months Ended
	Nov. 03, 2014 USD ($) project	Jul. 31, 2015 USD ($) item	Oct. 31, 2015 USD ($)	Jul. 31, 2014 USD ($)
Acquisitions
Number of acquisitions | item		3
Number of acquisitions where the allocation of the purchase price was considered preliminary | item		2
Net Assets
Goodwill		$ 241,951,000	$ 280,459,000	$ 231,647,000
International Medical Service S.r.l.
Acquisitions
Pre-acquisition annual revenues	$ 13,500,000
Total consideration for the transaction, excluding acquisition-related costs	24,610,000
Amount of assumed debt	2,498,000
Net Assets
Current assets	8,111,000
Property, plant and equipment	7,922,000
Other assets	177,000
Current liabilities	(5,735,000)
Deferred income tax liabilities	(3,028,000)
Other long-term liabilities	(1,020,000)
Net assets acquired	$ 13,477,000
Amortizable intangible assets, useful life	9 years
Number of in-process research and development projects acquired | project	0
Goodwill	$ 11,133,000
Goodwill deductible for income tax purposes	0
International Medical Service S.r.l. | Customer relationships
Net Assets
Amortizable intangible assets	$ 5,669,000
Amortizable intangible assets, useful life	9 years
International Medical Service S.r.l. | Technology
Net Assets
Amortizable intangible assets	$ 1,381,000
Amortizable intangible assets, useful life	9 years