Equity Investments (Distributions From Equity Investments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	$ 2,660	$ 6,350
Deepwater Gateway, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	1,500	2,150
Independence Hub, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	$ 1,160	$ 4,200

Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities.

No definition available.

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