EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2014	May 31, 2013
Earnings Per Share [Abstract]
Net income from continuing operations	$ 21,320	$ 18,539	$ 71,030	$ 63,426
Less: Allocation of income to unvested stockholders	(348)	(372)	(1,296)	(1,344)
Net earnings available to common stockholders	$ 20,972	$ 18,167	$ 69,734	$ 62,082
Basic weighted average shares outstanding	29,784	29,683	29,733	29,634
Add dilutive effect of stock options (two-class method)	8	9	10	10
Diluted average shares outstanding	29,792	29,692	29,743	29,644
Basic income per share from continuing operations	$ 0.70	$ 0.61	$ 2.35	$ 2.09
Diluted income per share from continuing operations	$ 0.70	$ 0.61	$ 2.34	$ 2.09