Equity Investments (Details) (USD $)	12 Months Ended							3 Months Ended		12 Months Ended
	Dec. 31, 2013 ft item	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Deepwater Gateway, L.L.C. [Member]	Dec. 31, 2012 Deepwater Gateway, L.L.C. [Member]	Dec. 31, 2013 Independence Hub, LLC [Member]	Dec. 31, 2012 Independence Hub, LLC [Member]	Jun. 30, 2012 Clough Helix JV [Member]	Mar. 31, 2012 Clough Helix JV [Member]	Dec. 31, 2011 Clough Helix JV [Member]
Number Of Equity Investments	2
Equity method investment, ownership percentage				50.00%		20.00%		50.00%		50.00%
Equity investments in unconsolidated affiliates	$ 157,919,000	$ 167,599,000		$ 85,800,000	$ 91,400,000	$ 72,100,000	$ 76,200,000
Capitalized interest				1,300,000	1,300,000	4,300,000	4,600,000
Water Depth	8,000
Equity in earnings of investments	2,965,000	8,434,000	22,215,000					3,700,000	(3,800,000)	2,100,000
Contributions to equity investments										2,700,000
Exit Fee									3,000,000
Other than temporary loss on equity investments			$ 10,563,000