Reconciliation of Statutory Federal Tax to Actual Provision (Benefit) For Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010	Aug. 21, 2010
Reconciliation Of Statutory Federal Tax Rate [Line Items]
Statutory tax rate	35.00%	35.00%		35.00%
Statutory tax on income	$ (1,666)	$ (1,682)		$ (5,016)
State taxes, net of federal benefit	219	52		33
Non-deductible expenses related to preferred stock	4,547	2,687		1,020
Research credit	(73)	(195)		(54)
Ethanol credit		(975)		(975)
Foreign tax loss with no benefit	(38)	200		34
Prior year true up	95	79		306
Unrecognized tax benefits	(165)	67		(139)
Valuation allowance	1,787
Other	100	80		89
Total provision (benefit)	$ 4,806	$ 313	$ (4,702)	$ (4,702)

Income Tax Reconciliation, Nondeductible Expense, Related To Preferred Stock

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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-Glossary Income Tax Expense (or Benefit)

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the current period and the expected income tax expense or benefit computed attributable to revisions of previously reported income tax expense.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in all income tax contingencies, whether recorded or adjusted, during the period.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to investment tax credits generated or utilized under enacted tax laws during the period.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to research tax credits generated or utilized under enacted tax laws during the period.

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