Net Earnings Per Share (Schedule Of Computation Of Basic And Diluted Net Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2017	Feb. 29, 2016	Feb. 28, 2017	Feb. 29, 2016
Net Earnings Per Share [Abstract]
Net earnings (loss)	$ 5,012	$ (4,129)	$ 5,885	$ 2,815
Weighted average shares outstanding	10,657	11,024	10,647	11,142
Diluted effect of stock awards	17		23	21
Weighted average shares outstanding assuming dilution	10,674	11,024	10,670	11,163
Basic net earnings (loss) per share	$ 0.47	$ (0.37)	$ 0.55	$ 0.25
Diluted net earnings (loss) per share	$ 0.47	$ (0.37)	$ 0.55	$ 0.25