Equity Method Investments (Detail) - The Company’s Investment in Joint Ventures (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013 Interest [Member]	Dec. 31, 2013 Interest [Member] Illinois Corn Processings, LLC [Member]	Dec. 31, 2013 Interest [Member] DMI [Member]	Dec. 31, 2012 Interest [Member]	Dec. 31, 2012 Interest [Member] Illinois Corn Processings, LLC [Member]	Dec. 31, 2012 Interest [Member] DMI [Member]
Schedule of Equity Method Investments [Line Items]
Intestments In joint ventures	$ 7,123	$ 6,653	$ 470	$ 7,301	$ 6,898	$ 403

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570

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Balance Type:	debit
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