Investment In And Loans To Dynamic Fuels (Narrative) (Details) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended						1 Months Ended
	Jan. 03, 2013	Jun. 27, 2012 lb	Dec. 31, 2012 gal	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010	Feb. 15, 2013	Dec. 31, 2011	Feb. 19, 2013 Dynamic Fuels, LLC [Member]	Jun. 27, 2012 Tyson Foods, Inc [Member]	Feb. 19, 2013 Tyson Foods, Inc [Member]
Unusual Risk or Uncertainty [Line Items]
Total estimate of maximum exposure to loss			$ 38,659,000
Equity investment in and loans to Dynamic Fuels, LLC			38,407,000					38,643,000
Current accounts receivable from Dynamic Fuels, LLC			252,000
Excess value of investment in Dynamic Fuels, LLC			8,000,000
Renewable products sold			63,000,000
Plant design production rate per year			75,000,000
Plant production as a percentage of design capacity				49.00%	35.00%
Noncurrent receivable from Dynamic Fuels								2,624,000
Additional investment to settle obligations of related party		6,597,000								6,597,000
Increase of price per pound of feedstock		0.01
Feedstock available for purchase under agreement		1,100,000,000
Tax credit per gallon of produced renewable diesel	1.00
Tax credit per gallon of produced alternative fuels	0.50
Tax refund receivable			23,000,000
Working capital loan							2,300,000				2,300,000
Technical services and royalty revenue				6,017,000	1,895,000	2,005,000
Total working capital contributions									4,600,000
Revenue recognized			$ 3,700,000