Derivative Financial Instruments (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Summary of location and aggregate fair value of all derivative financial instruments recorded in the consolidated statements of operations
Realized (loss) gain on derivatives	$ (701)	$ (1,165)	$ (5,458)	$ (519)
Unrealized gain (loss) on derivatives	16,293	(9,327)	7,950	(6,626)
Total	15,592	(10,492)	2,492	(7,145)
Revenues [Member]
Summary of location and aggregate fair value of all derivative financial instruments recorded in the consolidated statements of operations
Realized (loss) gain on derivatives	(701)	(1,165)	(5,458)	(519)
Unrealized gain (loss) on derivatives	16,293	(9,327)	7,950	(6,626)
Oil [Member] | Revenues [Member]
Summary of location and aggregate fair value of all derivative financial instruments recorded in the consolidated statements of operations
Realized (loss) gain on derivatives	(816)	(1,519)	(4,523)	(1,984)
Unrealized gain (loss) on derivatives	14,106	(8,132)	6,359	(6,818)
Natural Gas [Member] | Revenues [Member]
Summary of location and aggregate fair value of all derivative financial instruments recorded in the consolidated statements of operations
Realized (loss) gain on derivatives	19	161	(757)	790
Unrealized gain (loss) on derivatives	1,933	57	1,362	(132)
NGL's [Member] | Revenues [Member]
Summary of location and aggregate fair value of all derivative financial instruments recorded in the consolidated statements of operations
Realized (loss) gain on derivatives	96	193	(178)	675
Unrealized gain (loss) on derivatives	$ 254	$ (1,252)	$ 229	$ 324