Income Taxes (Reconciliation Of Unrecognized Tax Benefits) (Details) (USD $)	12 Months Ended
Aug. 31, 2011	Aug. 31, 2010
Income Taxes [Abstract]
Unrecognized income tax benefits	$ 7,346,000	$ 6,437,000
Additions based on tax positions related to the current year	1,258,000	1,301,000
Additions for tax positions of prior years	1,493,000	469,000
Lapse of statue of limitations	(964,000)	(861,000)
Reductions from settlements with taxing authorities	(1,929,000)	0
Unrecognized income tax benefits	7,204,000	7,346,000
Payment of interest	$ 400,000	$ 500,000

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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This element represents interest expense recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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