Reconciliation of the Total Amounts of Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Schedule of Unrecognized Tax Benefits [Line Items]
Unrecognized Tax Benefit - Opening Balance	$ 3,053	$ 3,526	$ 2,959
Gross increases - tax positions in prior period	878		200
Gross decreases - tax positions in prior period	(211)	(233)
Gross increases - tax positions in current period
Settlements		(193)
Restoration of statute of limitations due to 5 year NOL carry back			1,809
Lapse of statute of limitations		(47)	(1,442)
Unrecognized Tax Benefit - Ending Balance	$ 3,720	$ 3,053	$ 3,526

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Unrecognized Tax Benefits, Increase, Resulting From Other

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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 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 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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