Note 14 - Derivative Instruments and Fair Value Measurements (Detail) (USD $) In Thousands, unless otherwise specified			1 Months Ended	12 Months Ended		6 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Feb. 29, 2012 De Designated [Member]	Dec. 31, 2012 De Designated [Member]	Dec. 31, 2012 Grind Bushels Of Corn Per Month [Member] bu	Dec. 31, 2011 Cash Flow Hedge Ineffectiveness [Member]	Dec. 31, 2012 Cash Flow Hedge Ineffectiveness [Member]	Dec. 31, 2011 Bushels of Corn [Member]
Derivative, Hedge Designation			100 percent	100 percent
Processing Plants Current Output (in US Bushels)					1,750,000
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	$ (27)	$ (1,252)						$ (127)
Loss on Cash Flow Hedge Ineffectiveness						(586)	200
Restricted Cash and Investments	12	7,605
Collateralized Agreements	$ 0	$ 4,680