Note 16. Income Taxes (Detail) - Reconciliation of Unrecognized Tax Benefits (USD $) In Thousands, unless otherwise specified	12 Months Ended
Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Unrecognized income tax benefits	$ 7,204	$ 7,346	$ 6,437
Additions based on tax positions related to the current year	691	1,258	1,301
Additions for tax positions of prior years	470	1,493	469
Statute of limitations lapse	(613)	(964)	(861)
Reductions from settlements with taxing authorities	(2,288)	(1,929)
Unrecognized income tax benefits	$ 5,464	$ 7,204	$ 7,346

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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