Note 14 - Employee Stock Option and Retirement Plans (Details) - Summary of Restricted Stock Award (USD $)	0 Months Ended				12 Months Ended
	Apr. 08, 2013	Apr. 14, 2011	Nov. 08, 2010	Feb. 09, 2010	Aug. 31, 2014		Aug. 31, 2013		Aug. 31, 2012	Aug. 30, 2011
Summary of Restricted Stock Award [Abstract]
Balance As Of					358,000		383,000			407,000
Balance As Of					$ 80.43		$ 71.34			$ 71.31
Granted (restricted stock and stock units)	26,344	29,087	62,544	17,230	204,000		132,000
Granted (restricted stock and stock units)					$ 101.95		$ 85.80
Vested					(135,205)	[1]	(150,000)	[2]	(14,258)
Vested					$ 84.48	[1]	$ 62.34	[2]	$ 69.02
Canceled/forfeited					(59,000)		(7,000)		(10,000)
Canceled/forfeited					$ 86.39		$ 81.38		$ 77.13
Balance As Of					368,000		358,000		383,000	407,000
Balance As Of					$ 89.77		$ 80.43		$ 71.34	$ 71.31

[1] The 135,205 restricted stock awards that vested during fiscal 2014 were comprised of: 62,544 of awards granted on November 8, 2010, which cliff vested 60% after three years (on November 8, 2013) with the remaining 40% cliff vesting after five years (on November 8, 2015) 29,087 of awards granted on April 14, 2011, which vested 100% after three years on April 14, 2014 26,344 restricted stock awards that were granted on April 8, 2013, which cliff vest 20% annually upon the anniversary date of the grant and 17,230 awards relating to restricted stock granted on February 9, 2010 which cliff vested 50% after four years (on February 9, 2014) and the remaining 50% vesting after six years on February 9, 2016.

[2] Of the total 149,741 restricted stock awards that vested during fiscal 2013, 87,758 related to awards granted on October 23, 2009. These restricted stock awards cliff vested 60% after three years (on October 23, 2012) and the remaining 40% will vest after five years (on October 23, 2014). An additional 55,572 awards that vested in fiscal 2013 related to awards granted on February 9, 2010 which cliff vested 100% after three years (on February 9, 2013). The remaining 6,411 restricted stock awards that vested were previously granted between June 2010 and July 2011 and vesting occurred when certain ASV targets were met in fiscal 2013.