Supplemental Oil and Gas Disclosures (Unaudited) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Results of Operations for Producing Activities Detail [Table]
Oil and gas sales revenues	$ 2,438	$ 4,722	$ 5,560
Production (lifting) costs	921	2,002	2,637
Depreciation, depletion, and amortization	0	30	37
Excess decommissioning and abandonment costs	2,665	73,194	75,313
Accretion expense	$ 1,375	130	87
Gain on insurance recoveries		(6)	(5,685)
Pretax income (loss) from producing activities	$ (2,523)	(70,628)	(66,829)
Income tax expense (benefit)	0	0	(23,390)
Results of oil and gas producing activities	$ (2,523)	$ (70,628)	$ (43,439)