Note 11 - Common Stock and Earnings Per Share (Details) - Shares of Common Stock Outstanding	3 Months Ended
	Nov. 30, 2014		Nov. 30, 2013
Class of Stock [Line Items]
Balance at September 1	41,792,802		43,324,000
Common stock issued for employee stock plans	183,000		215,000
Repurchase of common stock	(379,854)
Balance at November 30, 2014 and 2013, respectively	41,578,905		42,988,000
Repurchase of Common Stock from Employees [Member]
Class of Stock [Line Items]
Repurchase of common stock	(17,000)	[1]	(21,000)	[1]
Share Repurchase Program [Member]
Class of Stock [Line Items]
Repurchase of common stock	(380,000)		(530,000)

[1] For the three months ended November 30, 2014 and 2013, the Company repurchased 17,165 and 20,777 shares, or $2.2 million and $2.3 million, of common stock, respectively, in settlement of employee tax withholding obligations due upon the vesting of restricted stock.