Note 14. Employee Stock Option and Retirement Plans (Detail) - Changes to the Current Estimate of the Vesting Percentage and Related Expense (USD $) In Thousands, unless otherwise specified		12 Months Ended
	Jul. 31, 2011	Aug. 31, 2012 July 2012 Performance Based Option Grant Review [Member] Financial Performance Level One [Member]	Aug. 31, 2012 July 2012 Performance Based Option Grant Review [Member] Financial Performance Level Two [Member]	Aug. 31, 2012 July 2012 Performance Based Option Grant Review [Member] Financial Performance Level Three [Member]	Aug. 31, 2012 July 2012 Performance Based Option Grant Review [Member] Financial Performance Level Four [Member]	Aug. 31, 2012 July 2012 Performance Based Option Grant Review [Member] Financial Performance Level Five [Member]	Aug. 31, 2012 July 2012 Performance Based Option Grant Review [Member] Financial Performance Level Six [Member]
Vesting Percentage	25.00%	0.00%	20.00%	40.00%	60.00%	80.00%	100.00%
Cumulative Catch-up Adjustment		$ (84)	$ 0	$ 136	$ 200	$ 257	$ 330
Remaining Expense to be Recognized		$ 0	$ 1,516	$ 3,064	$ 4,600	$ 6,143	$ 7,670