Fair Value Measurements (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Assets (Liabilities)
Lease and well equipment inventory	$ 923	$ 785
Fair value on a non-recurring basis [Member]
Assets (Liabilities)
Total	(1,847)	(1,470)
Fair value on a non-recurring basis [Member] | Asset retirement obligations [Member]
Assets (Liabilities)
Asset retirement obligations	(1,847)	(1,470)
Fair value on a non-recurring basis [Member] | Level 1 [Member]
Assets (Liabilities)
Total
Fair value on a non-recurring basis [Member] | Level 1 [Member] | Asset retirement obligations [Member]
Assets (Liabilities)
Asset retirement obligations	0	0
Fair value on a non-recurring basis [Member] | Level 2 [Member]
Assets (Liabilities)
Total
Fair value on a non-recurring basis [Member] | Level 2 [Member] | Asset retirement obligations [Member]
Assets (Liabilities)
Asset retirement obligations	0	0
Fair value on a non-recurring basis [Member] | Level 3 [Member]
Assets (Liabilities)
Total	(1,847)	(1,470)
Fair value on a non-recurring basis [Member] | Level 3 [Member] | Asset retirement obligations [Member]
Assets (Liabilities)
Asset retirement obligations		(1,470)
Asset Retirement Obligation, Period Increase (Decrease)	$ (1,847)