Components of Inventory Balances (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Inventory [Line Items]
Finished goods	$ 623	$ 192
Work in process	228	224
Spare parts	1,424	1,195
Total inventories	4,027	3,581
Corn
Inventory [Line Items]
Raw materials	1,376	1,456
Enzymes And Other Inputs
Inventory [Line Items]
Raw materials	$ 376	$ 514

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

+ References

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Gross amount of components of assembled products that can be sold directly or indirectly through sales of assembled products.

+ References

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