Summary of Fair Values of Separately Identifiable Assets Acquired and Liabilities Assumed (Detail) (USD $)								0 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Mar. 02, 2013 Ultrasonix		Mar. 02, 2013 Ultrasonix Developed technologies	Mar. 02, 2013 Ultrasonix Customer relationships	Mar. 02, 2013 Ultrasonix Tradenames	Sep. 20, 2013 PocketSonics	Jul. 31, 2014 PocketSonics	Sep. 20, 2013 PocketSonics	Sep. 20, 2013 PocketSonics In-process research and development
Business Acquisition [Line Items]
Cash			$ 400,000							$ 500,000
Goodwill	56,955,000	50,073,000	48,200,000						2,800,000	6,900,000
Intangible assets			25,300,000		5,900,000	18,500,000	900,000				11,500,000
Total assets acquired			93,100,000							18,900,000
Accounts payable and accrued expenses			(5,400,000)							(300,000)
Deferred taxes			(4,700,000)							(4,100,000)
Total liabilities assumed			(12,800,000)							(4,400,000)
Total purchase price			80,300,000							14,500,000
Cash consideration paid								11,100,000
Fair value of contingent consideration									2,100,000	1,900,000
Previously held equity interest in PocketSonics								1,500,000
Total purchase price								14,500,000
Accounts receivable			6,500,000	[1]
Inventory			9,400,000	[2]
Prepaids and other assets			2,900,000
Property, plant, and equipment			300,000
Other assets			100,000
Deferred revenue			(800,000)	[2]
Accrued warranty			(1,100,000)
Debt			$ (800,000)

[1] The gross amount due is $8.7 million, of which $2.2 million is expected to be uncollectible. We did not acquire any other class of receivables other than trade receivables as a result of the acquisition of Ultrasonix.

[2] The inventory fair value adjustment of $3.7 million associated with the acquisition was fully amortized as of October 31, 2013. The deferred revenue adjustment of $0.8 million associated with the acquisition will be amortized over 4.5 years. The inventory fair value and deferred revenue adjustments were recognized in Product cost of sales and Net product revenue in our Consolidated Statement of Operations, respectively.