Derivative Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Purity Ethane contract 1 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Purity Ethane contract 2 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Propane contract 1 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Propane contract 2 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Normal Butane contract 1 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Normal Butane contract 2 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Isobutane contract 1 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Isobutane contract 2 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Natural Gasoline contract 1 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Natural Gasoline contract 2 [Member]	Dec. 31, 2012 NGL's [Member] Open Swap Contract [Member] Natural Gasoline contract 3 [Member]
Open Swap Contracts For Natural Gas Liquid
Calculation Period				01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013	01-01-2013 - 12-31-2013
Notional Quantity				110,000	110,000	53,000	53,000	14,700	14,700	7,000	7,000	12,000	12,000	12,000
Fixed Price				0.335	0.355	0.953	1.001	1.455	1.560	1.515	1.625	2.025	2.085	2.102
Fair Value of Asset (Liability)	$ 4,479	$ 9,282	$ 225	$ 106	$ 133	$ 13	$ 43	$ (29)	$ (10)	$ (18)	$ (9)	$ (8)	$ 1	$ 3