Note 13. Employee Stock Option and Retirement Plans (Detail) - Changes to the Current Estimate of the Vesting Percentage and Related Expense (July 2012 Performance Based Option Grant Review [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Nov. 30, 2012
Financial Performance Level One [Member]
Vesting Percentage	0.00%
Cumulative Catch-up Adjustment	$ (211)	[1]
Financial Performance Level Two [Member]
Vesting Percentage	20.00%
Cumulative Catch-up Adjustment	0	[1]
Remaining Expense to be Recognized	1,389
Financial Performance Level Three [Member]
Vesting Percentage	40.00%
Cumulative Catch-up Adjustment	129	[1]
Remaining Expense to be Recognized	2,860
Financial Performance Level Four [Member]
Vesting Percentage	60.00%
Cumulative Catch-up Adjustment	289	[1]
Remaining Expense to be Recognized	4,300
Financial Performance Level Five [Member]
Vesting Percentage	80.00%
Cumulative Catch-up Adjustment	432	[1]
Remaining Expense to be Recognized	5,758
Financial Performance Level Six [Member]
Vesting Percentage	100.00%
Cumulative Catch-up Adjustment	614	[1]
Remaining Expense to be Recognized	$ 7,176

[1] Amounts represent the cumulative catch-up adjustment to be recorded if there was a change in the vesting percentage as of November 30, 2012.