Oil And Gas Properties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Oil And Gas Properties [Abstract]
Oil and gas properties, at cost, net of impairment	$ 8,286	$ 49,388
Unevaluated properties, at cost	552	462
Accumulated depreciation, depletion and amortization		(24,437)
Oil and gas properties, net	8,838	25,413
Depletion expense	$ 2,500	$ 2,800	$ 2,600