Asset Retirement Obligation - Asset Retirement Obligation Summary (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Asset Retirement Obligation Disclosure [Abstract]
Oil and gas producing properties - asset retirement obligation	$ 2	[1]	$ 2
Estimated well life	27 years 6 months

[1] This is a recurring Level 3 fair value measurement. See Note 7 - "Fair Value Measurements" for further discussions of Level 3 valuation definitions.