Income Tax (Details 4) (USD $) In Thousands	12 Months Ended
Aug. 31, 2011	Aug. 31, 2010	Aug. 31, 2009
Income Tax [Abstract]
Unrecognized Tax Benefits, Beginning Balance	$ 20,367	$ 1,532	$ 4,223
Change in tax positions of current year	2,440	1,640
Change for tax positions of prior years	(12,045)	17,302	(1,426)
Reductions due to settlements with taxing authorities			(122)
Reductions due to statute of limitations lapse		(107)	(1,143)
Unrecognized Tax Benefits, Ending Balance	$ 10,762	$ 20,367	$ 1,532

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

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