Summary of Charges Related to Accrued Restructuring Activity (Detail) - USD ($) $ in Thousands		12 Months Ended
		Jul. 31, 2015		Jul. 31, 2014		Jul. 31, 2013
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	[1],[2]	$ 3,800		$ 2,800
Adjustments	[1],[2]	(400)
Restructuring Charge		(354)	[1],[2]	3,483	[1],[2]	$ 3,519
Cash payments	[1],[2]	(2,800)		(2,500)
Balance at end period	[1],[2]	600		3,800		2,800
Employee Severance and Benefits
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	[3]	2,900		1,800
Adjustments	[3]	(300)
Restructuring Charge	[3]			2,600
Cash payments	[3]	(2,400)		(1,500)
Balance at end period	[3]	200		2,900		1,800
Facility Exit Costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	[4]	800		200
Adjustments	[4]	(100)
Restructuring Charge	[4]			800
Cash payments	[4]	(300)		(200)
Balance at end period	[4]	400		800		200
Acquisition Related Charges
Restructuring Cost and Reserve [Line Items]
Balance at beginning period		100		800
Restructuring Charge				100
Cash payments		$ (100)		(800)
Balance at end period				$ 100		$ 800

[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.

[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] 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. Cash payments in fiscal year 2015 pertain only to the closure of the Englewood Colorado facility.