Fair Value Measurements (Details) (Fair value on a recurring basis [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets (Liabilities)
Total	$ 55,549	$ (2,753)
Natural Gas [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives	55,549	192
Oil [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives		(2,945)
Level 1 [Member]
Assets (Liabilities)
Total	0	0
Level 1 [Member] | Natural Gas [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives	0	0
Level 1 [Member] | Oil [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives		0
Level 2 [Member]
Assets (Liabilities)
Total	55,549	(2,753)
Level 2 [Member] | Natural Gas [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives	55,549	192
Level 2 [Member] | Oil [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives		(2,945)
Level 3 [Member]
Assets (Liabilities)
Total	0	0
Level 3 [Member] | Natural Gas [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives	0	0
Level 3 [Member] | Oil [Member]
Assets (Liabilities)
Oil, natural gas and NGL derivatives		$ 0