Reportable Segment Information (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Oct. 31, 2015	Oct. 31, 2014	Jul. 31, 2015	Jul. 31, 2014
Segment Reporting Information [Line Items]
Restructuring Charge	$ 3,283	$ (58)
Cash and cash equivalents	130,506	$ 116,443	$ 123,800	$ 114,540
Corporate
Segment Reporting Information [Line Items]
Cash and cash equivalents	86,200		86,200
Medical Imaging
Segment Reporting Information [Line Items]
Restructuring Charge	2,000		(200)
Ultrasound
Segment Reporting Information [Line Items]
Restructuring Charge	700		(100)
Security Technology
Segment Reporting Information [Line Items]
Restructuring Charge	$ 600		$ (100)