Business Combination - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended		3 Months Ended			5 Months Ended	12 Months Ended		12 Months Ended
	Nov. 19, 2010	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2013 Ultrasonix Acquisition	Apr. 30, 2013 Ultrasonix Acquisition	Jan. 31, 2013 Ultrasonix Acquisition	Jul. 31, 2013 Ultrasonix Acquisition	Jul. 31, 2013 Ultrasonix Acquisition	Mar. 02, 2013 Ultrasonix Acquisition	Jul. 31, 2013 Ultrasonix Acquisition General and Administrative
Business Acquisition [Line Items]
Purchase price, net of cash acquired									$ 79,932
Weighted average amortization period for intangible assets								10 years
Business Acquisition, Goodwill Expected Tax Deductible Period								15 years
Acquisition related cost				3,057	1,880	663				5,600
Inventory step up amortization										3,033
Intangible and deferred revenue amortization										1,357
Legal and due diligence related expenses										1,210
Revenue from acquired business							10,095
Net earnings from acquisition business							(5,777)
Amortization of trade name, developed technology, customer relationships and inventory fair value and deferred revenue adjustments from purchase accounting		4,791	7,842
Adjustment of acquisition related expenses		1,210
Total purchase consideration	686								80,298
Cash paid	346
Contingent consideration	340
Period during which the company will generate revenue from sale of certain acquired products	2 years
Contingent consideration			$ 435