Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Property Plant And Equipment [Abstract]
Wells and production facilities	$ 43,924	$ 28,874
Proved properties	386,196	386,196
Work in progress and other	188,288	86,634
Oilfield assets	618,408	501,704
Accumulated depletion	(105,342)	(74,909)
Oilfield assets, net	513,066	426,795
Unevaluated leaseholds	8,240	8,240
Oil and gas properties, net	521,306	435,035
Other property and equipment	2,204	1,590
Accumulated depreciation	(1,145)	(838)
Other property and equipment, net	1,059	752
Total property, plant and equipment, net	$ 522,365	$ 435,787