Net Income (Loss) Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Nov. 30, 2012	Nov. 30, 2011
Earnings Per Share [Abstract]
Net income (loss)	$ (1,443)	$ 7,745
Net income attributable to noncontrolling interests	(228)	(727)
Net income (loss) attributable to SSI	$ (1,671)	$ 7,018
Computation of shares:
Weighted average common shares outstanding, basic	26,567,000	27,451,000
Incremental common shares attributable to dilutive stock options, performance share awards, DSUs and RSUs	0	264,000
Weighted average common shares outstanding, diluted	26,567,000	27,715,000
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	864,874	351,074