Disclosures About Capitalized Costs, Costs Incurred (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Company:
Proved properties	$ 1,122	$ 1,122
Company
Company:
Unproved properties	0	0
Proved properties	1,122	1,122
Oil and Gas Property, Successful Effort Method, Gross, Total	1,122	1,122
Accumulated depreciation and depletion	(930)	(862)
Oil and gas property, successful efforts method	192	260
Company's Share of Laramie Energy
Company:
Unproved properties	14,416	9,253
Proved properties	334,085	202,195
Oil and Gas Property, Successful Effort Method, Gross, Total	348,501	211,448
Accumulated depreciation and depletion	(91,454)	(56,241)
Oil and gas property, successful efforts method	$ 257,047	$ 155,207