Changes in Accumulated Other Comprehensive Income (Detail) (USD $)	6 Months Ended								6 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2014 Unrealized Gains (Losses) on Foreign Currency Forward Contracts	Jan. 31, 2013 Unrealized Gains (Losses) on Foreign Currency Forward Contracts	Jan. 31, 2014 Unrealized Gains (Losses) on Pension Plan	Jul. 31, 2013 Unrealized Gains (Losses) on Pension Plan	Jan. 31, 2013 Unrealized Gains (Losses) on Pension Plan	Jul. 31, 2012 Unrealized Gains (Losses) on Pension Plan	Jan. 31, 2014 Currency Translation	Jan. 31, 2013 Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income,Net of Tax, Beginning balance	$ 9,148,000	$ 2,300,000	$ (100,000)		$ (2,300,000)	$ (2,300,000)	$ (4,700,000)	$ (4,700,000)	$ 11,500,000	$ 7,000,000
Pre-tax change before reclass to earnings	800,000	(1,700,000)		(100,000)					800,000	(1,600,000)
Amount reclassed to earnings (Note 9)	100,000	100,000	100,000	100,000
Income tax benefit	100,000	7,300,000							100,000	7,300,000
Accumulated Other Comprehensive Income, Net of Tax, Ending balance	$ 10,055,000	$ 8,000,000			$ (2,300,000)	$ (2,300,000)	$ (4,700,000)	$ (4,700,000)	$ 12,400,000	$ 12,700,000