Discontinued Operations (Details) (USD $) In Thousands	12 Months Ended
Aug. 31, 2011	Aug. 31, 2010	Aug. 31, 2009
Financial information for discontinued operations
Current assets	$ 224	$ 10,850	$ 60,594
Noncurrent assets	10,775	27,045	79,861
Current liabilities	7,862	14,723	25,885
Noncurrent liabilities	0	22	72
Revenue	1,369	122,971	474,056
Earnings (loss) before taxes	$ (2,965)	$ (59,762)	$ 31,991

The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for current assets (assets with expected useful life shorter than one year or one operating cycle, whichever is longer) of a disposal group, including a component of the entity (discontinued operation), to be sold or that has subsequently been disposed of through sale, as of the financial statement date.

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The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for noncurrent assets (assets with expected useful life longer than one year or one operating cycle, whichever is longer) of a disposal group, including a component of the entity (discontinued operation), to be sold or that has subsequently been disposed of through sale, as of the financial statement date.

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Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Carrying value as of the balance sheet date of current obligations (due less than one year or one operating cycle, if longer) arising from the sale, disposal or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

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Carrying value of noncurrent obligations (due more than one year or one operating cycle, whichever is longer) relating to the sale, disposal or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation), as of the balance sheet date.

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