Quarterly Data (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Data [Abstract]
Revenues	$ 277	$ 373	$ 408	$ 899	$ 1,124	$ 4,342	$ 10,810	$ 1,250	$ 1,957	$ 17,526	$ 4,214
Operating income (loss)	(3,127)	(2,483)	(1,719)	(2,009)	(797)	2,037	8,763	(786)	(9,338)	9,217	(3,049)
Income (loss) from Dynamic Fuels investment	(3,526)	(3,252)	(1,498)	6,707	(4,275)	(2,752)	(2,155)	(830)	(1,569)	(10,012)	(13,880)
Net income (loss) from continuing operations	(5,993)	(5,999)	(1,286)	4,634	(5,059)	(1,037)	6,956	(1,923)	(8,644)	(1,063)	(16,922)
Net income (loss) from discontinued operations				6,391	(10)	(9)	(9)	(10)	6,391	(38)	(27)
Net income (loss)	$ (5,993)	$ (5,999)	$ (1,286)	$ 11,025	$ (5,069)	$ (1,046)	$ 6,947	$ (1,933)	$ (2,253)	$ (1,101)	$ (16,949)
Continuing operations	$ (0.60)	$ (0.60)	$ (0.13)	$ 0.48	$ (0.50)	$ (0.11)	$ 0.70	$ (0.20)	$ (0.87)	$ (0.11)	$ (1.89)
Discontinued operations	$ 0.00	$ 0.00	$ 0.00	$ 0.67	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.64
Net income (loss)	$ (0.60)	$ (0.60)	$ (0.13)	$ 1.15	$ (0.50)	$ (0.11)	$ 0.70	$ (0.20)	$ (0.23)	$ (0.11)	$ (1.89)