Business Combinations - Additional Information (Detail) - USD ($)				3 Months Ended		12 Months Ended
	Jan. 08, 2016	May 30, 2014	Sep. 30, 2013	Jan. 31, 2016	Oct. 31, 2013	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014	Oct. 28, 2014	Sep. 20, 2013	Apr. 30, 2010
Business Acquisition [Line Items]
Estimated (decreases) in contingent consideration						$ 141,000	$ (62,000)	$ 125,000
Business acquisition, goodwill						$ 73,915,000	57,450,000
Oncura
Business Acquisition [Line Items]
Purchase price	$ 20,200,000
Contingent consideration	10,100,000
Amount merger consideration paid	8,400,000
Business combination post closing adjustment	400,000
Relief of debt owed to Analogic	$ 1,300,000
Business Acquisition Contingent Consideration Payment Period	4 years
Business Acquisition Contingent Consideration Payment Start Date	May 01, 2016
Business Acquisition, Goodwill Expected Tax Deductible Period						15 years
Acquisition related charges				$ 400,000		$ 400,000
Intangible assets	$ 4,100,000
Estimated (decreases) in contingent consideration						$ 100,000
Business acquisition, goodwill	$ 16,400,000
Pathfinder Therapeutics Inc
Business Acquisition [Line Items]
Purchase price									$ 1,600,000
Business Acquisition, Goodwill Expected Tax Deductible Period						15 years
Acquisition related charges							100,000
Weighted average amortization period for intangible assets						7 years 7 months 6 days
Intangible assets									1,100,000
Business acquisition, goodwill									$ 400,000
PocketSonics
Business Acquisition [Line Items]
Purchase price										$ 14,500,000
Contingent consideration			$ 1,900,000			$ 2,000,000	2,000,000			1,900,000
Amount merger consideration paid			$ 11,100,000
Acquisition related charges								100,000
Ownership interests											10.00%
Contingent consideration, range of outcomes, value, high										3,000,000
Estimated (decreases) in contingent consideration						$ 0	$ (100,000)
Business acquisition, goodwill										6,900,000
Loss from pre-acquisition equity interest					$ 500,000			$ 500,000
PocketSonics | In-process research and development
Business Acquisition [Line Items]
Amount of equity investment											$ 1,900,000
Intangible assets										$ 11,500,000
Intangible assets, estimated useful lives		10 years