Restructuring and Related Charges by Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2015		Jul. 31, 2014		Jul. 31, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring Charge	$ (354)	[1],[2]	$ 3,483	[1],[2]	$ 3,519
Medical Imaging
Restructuring Cost and Reserve [Line Items]
Restructuring Charge	(200)		1,700		1,100
Ultrasound
Restructuring Cost and Reserve [Line Items]
Restructuring Charge	(100)		1,400		2,200
Security and Detection
Restructuring Cost and Reserve [Line Items]
Restructuring Charge	$ (100)		$ 400		$ 200

[1] Activity in fiscal year 2014 pertains to both the Fiscal Year 2014 Restructuring Plan and the 2013 Restructuring Plan. In fiscal year 2014, the restructuring charges of $2.9 million relate to the Fiscal Year 2014 Restructuring Plan, while restructuring charges of $0.6 million and cash payments of ($2.5) million relate to the Fiscal Year 2013 Restructuring Plan.

[2] Activity in fiscal year 2015 pertains to both the Fiscal Year 2014 Restructuring Plan and the 2013 Restructuring Plan. In fiscal year 2015, the restructuring adjustments of ($0.3) million and cash payments of ($2.4) million relate to the Fiscal Year 2014 Restructuring Plan, while restructuring adjustments of ($0.1) million and cash payments of ($0.5) million relate to the Fiscal Year 2013 Restructuring Plan.