Summary of Charges Related to Accrued Restructuring Activity (Detail) (USD $)	3 Months Ended										3 Months Ended
	Oct. 31, 2014	Oct. 31, 2013		Oct. 31, 2014 Employee Severance and Benefits		Oct. 31, 2013 Employee Severance and Benefits	Oct. 31, 2014 Facility Exit Costs		Oct. 31, 2013 Facility Exit Costs	Jul. 31, 2013 Facility Exit Costs	Oct. 31, 2014 Acquisition Related Charges		Oct. 31, 2013 Acquisition Related Charges	Oct. 31, 2013 Restructuring Costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning period	$ 3,800,000	$ 2,800,000	[1]	$ 2,900,000	[2]	$ 1,800,000	$ 800,000	[3]	$ 200,000	$ 200,000	$ 100,000	[3]	$ 800,000
Restructuring Charge	58,000	39,000				200,000							100,000	300,000	[1]
Adjustments	(100,000)	(300,000)	[1]			(200,000)	(100,000)	[3]					(100,000)
Cash payments	(1,100,000)	(600,000)	[1]	(900,000)	[2]	(500,000)	(100,000)	[3]			(100,000)	[3]	(100,000)
Balance at end period	$ 2,600,000	$ 2,200,000	[1]	$ 2,000,000	[2]	$ 1,300,000	$ 600,000	[3]	$ 200,000	$ 200,000			$ 700,000

[1] All activity during the period pertains to the 2013 Restructuring Plan.

[2] All activity during the period pertains to the 2014 Restructuring Plan.

[3] All activity pertains to the 2013 Restructuring Plan.