Components of Provision (Benefit) for Income Taxes on Continuing Operations (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Current income taxes (benefit):
Federal	$ 3,403	$ 5,461	$ 7,723
State	541	534	344
Foreign	232	(37)	(183)
Current Income Tax Expense (Benefit), Total	4,176	5,958	7,884
Deferred income taxes (benefit):
Federal	(3,339)	(113)	(2,361)
State	25	167	107
Foreign	264	(1,700)	38
Benefit from deferred income taxes	(3,050)	(1,674)	(2,216)
Income Tax Expense (Benefit), Continuing Operations, Total	$ 1,126	$ 4,312	$ 5,668