Income from Continuing Operations Before Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Domestic	$ 30,249	$ 15,676	$ 16,336
Foreign	13,950	5,256	5,131
Income from continuing operations before income taxes	$ 44,199	$ 20,932	$ 21,467