Commitments and Contingencies (Details Textual) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended		12 Months Ended			6 Months Ended	12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 gal	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2013 Cargill [Member]	Dec. 31, 2010 Fairmont Plant [Member]	Dec. 31, 2008 Fairmont Plant [Member]	Jun. 30, 2013 Fairmont Plant [Member]	Jun. 30, 2013 Wood River Plant [Member]	Dec. 31, 2010 Wood River Plant [Member]	Dec. 31, 2008 Wood River Plant [Member]
Deferred Lease Payments	$ 1,600,000		$ 1,600,000
Subsidiaries Leasing Amount Per Year			6,700,000
Operating Lease Rent Expense Paid By Each Subsidiary Per Year					4,300,000
Operating Leases, Rent Expense	2,889,000	2,811,000	5,750,000	5,639,000
Origination Fee Per Bushel Under Lease Agreements			$ 0.048
Minimum Annual Origination Fee Payable	1,200,000		1,200,000			1,000,000
Number Of Bushels Contracted To Purchase									55,000	5,451,000
Percentage Of Purchase Commitments Of Projected Requirements										11.00%
Percentage Of Minimum Annual Commissions Payable In Average Selling Price			1.00%
Minimum Annual Operating Lease Payments							50,000	1,200,000			250,000	1,500,000
Number Of Gallons Of Ethanol			82,500,000
Deferred Ethanol Commissions	1,000,000		1,000,000
Initial Minimum Annual Lease Payments								800,000				1,000,000
Mileage Limit For Escalation Of Monthly Rental Charges	30,000		30,000
Term Of Operating Lease								20 years				20 years
Minimum Ethanol Commissions Payable	$ 600,000		$ 600,000