Note 13 - Employee Stock Option and Retirement Plans (Details) - Change in the Actual Financial Performance Level (USD $)	6 Months Ended
	Feb. 28, 2014
Note 13 - Employee Stock Option and Retirement Plans (Details) - Change in the Actual Financial Performance Level [Line Items]
Total unamortized stock-based compensation expense	$ 12,600,000
Financial Performance Level One [Member] | November 2012 Annual Employee Performance-Based Option Grant Review [Member]
Note 13 - Employee Stock Option and Retirement Plans (Details) - Change in the Actual Financial Performance Level [Line Items]
Vesting percentage	0.00%
Total unamortized stock-based compensation expense	0
One-time adjustment	(1,907,000)	[1]
Average remaining quarterly expense to be recognized	0
Financial Performance Level Two [Member] | November 2012 Annual Employee Performance-Based Option Grant Review [Member]
Note 13 - Employee Stock Option and Retirement Plans (Details) - Change in the Actual Financial Performance Level [Line Items]
Vesting percentage	20.00%
Total unamortized stock-based compensation expense	2,840,000
One-time adjustment	0	[1]
Average remaining quarterly expense to be recognized	194,000
Financial Performance Level Three [Member] | November 2012 Annual Employee Performance-Based Option Grant Review [Member]
Note 13 - Employee Stock Option and Retirement Plans (Details) - Change in the Actual Financial Performance Level [Line Items]
Vesting percentage	60.00%
Total unamortized stock-based compensation expense	8,521,000
One-time adjustment	3,814,000	[1]
Average remaining quarterly expense to be recognized	582,000
Financial Performance Level Four [Member] | November 2012 Annual Employee Performance-Based Option Grant Review [Member]
Note 13 - Employee Stock Option and Retirement Plans (Details) - Change in the Actual Financial Performance Level [Line Items]
Vesting percentage	100.00%
Total unamortized stock-based compensation expense	14,202,000
One-time adjustment	7,628,000	[1]
Average remaining quarterly expense to be recognized	$ 970,000

[1] Amounts represent the cumulative catch-up adjustment to be recorded if there was a change in the vesting percentage as of February 28, 2014.