Restructuring Charges - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		12 Months Ended										3 Months Ended
	May 31, 2013 Person	Jul. 31, 2013	Apr. 30, 2013	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2014 Medical Imaging	Jul. 31, 2013 Medical Imaging	Jul. 31, 2014 Ultrasound	Jul. 31, 2013 Ultrasound	Jul. 31, 2014 Security Technology	Jul. 31, 2013 Security Technology	Jul. 31, 2014 Restructuring Plan Two Thousand Thirteen	Jul. 31, 2014 Ultrasonix Employee	Jul. 31, 2014 Ultrasonix Medical Imaging	Jul. 31, 2014 Ultrasonix Ultrasound	Jul. 31, 2014 Ultrasonix Security Technology
Restructuring Cost and Reserve [Line Items]
Additional restructuring and related charges	$ 3,500,000	$ 3,000,000	$ 500,000	$ 3,483,000	$ 3,519,000		$ 1,700,000	$ 1,100,000	$ 1,400,000	$ 2,200,000	$ 400,000	$ 200,000	$ 600,000	$ 2,900,000	$ 1,900,000	$ 500,000	$ 500,000
Involuntarily terminated employees	115													48
Restructuring and related charges, net				$ 3,500,000	$ 3,500,000	$ 0