Summary of Charges Related to Accrued Restructuring Activity (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 31, 2014		Jul. 31, 2013
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	$ 2.8	[1],[2]	$ 0.3	[1],[2]
Restructuring Charge	3.5	[1],[2]	3.5	[1],[2]
Cash payments	(2.5)	[1],[2]	(1.0)	[1],[2]
Balance at end period	3.8	[1],[2]	2.8	[1],[2]
Employee Severance and Benefits
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	1.8	[3]	0.3	[3]
Restructuring Charge	2.6	[3]	2.5	[3]
Cash payments	(1.5)	[3]	(1.0)	[3]
Balance at end period	2.9	[3]	1.8	[3]
Facility Exit Costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	0.2	[4],[5]
Restructuring Charge	0.8	[4],[5]	0.2	[4],[5]
Cash payments	(0.2)	[4],[5]
Balance at end period	0.8	[4],[5]	0.2	[4],[5]
Aquisition Related Charges
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	0.8	[4]
Restructuring Charge	0.1	[4]	0.8	[4]
Cash payments	(0.8)	[4]
Balance at end period	$ 0.1	[4]	$ 0.8	[4]

[1] All activity prior to July 31, 2012 relates to the Fiscal Year 2011 Restructuring Plan. In fiscal year 2013, the restructuring charge of $3.5 million, and cash payments of $0.7 million relate to the Fiscal Year 2013 Restructuring Plan, while cash payments of $0.3 million relate to the Fiscal Year 2011 Restructuring Plan.

[2] 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.

[3] Restructuring Charges in fiscal year 2014, include $2.9 million with respect to the Fiscal Year 2014 Restructuring Plan. All other activity pertains to the Fiscal Year 2013 Restructuring Plan.

[4] Activity in fiscal year 2013 pertains to the Fiscal Year 2013 Restructuring Plan with respect to the Ultrasonix acquisition.

[5] Restructuring Charges in fiscal year 2014 pertains to the Fiscal Year 2013 Restructuring Plan with respect to the closure of the Englewood Colorado facility. Cash payments in Fiscal Year 2014 pertain to both the closure of the Englewood Colorado facility and the Ultrasonix sales subsidiary in Paris, France.