Restructuring and Related Charges by Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Oct. 31, 2014	Oct. 31, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring and related charges, net	$ (0.1)
Medical Imaging
Restructuring Cost and Reserve [Line Items]
Restructuring and related charges, net		(0.1)
Ultrasound
Restructuring Cost and Reserve [Line Items]
Restructuring and related charges, net	$ (0.1)	$ 0.1