Equity Investments (Distributions From Equity Investments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	$ 2,800	$ 2,660
Deepwater Gateway, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	2,000	1,500
Independence Hub, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	$ 800	$ 1,160

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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