Investments in Unconsolidated Affiliates (Details 2) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Summarized financial information of other unconsolidated investments
Equity in (loss) earnings from unconsolidated affiliates	$ (161,589)	$ 2,049	$ (158,581)	$ (19,788)
Distributions			17,961	16,999
Other Unconsolidated Investments [Member]
Summarized financial information of other unconsolidated investments
Operating revenue			21,283	24,112
Operating expenses			(17,887)	(20,132)
Depreciation and amortization			(1,394)	(1,137)
Other income, net				3
Net income (loss)			2,002	2,846
Equity in (loss) earnings from unconsolidated affiliates			1,743	2,123
Distributions			2,212	2,427
Contributions			27,391
Current assets	5,306	4,278	5,306	4,278
Noncurrent assets	71,471	20,847	71,471	20,847
Current liabilities	(6,876)	(5,594)	(6,876)	(5,594)
Noncurrent liabilities	(170)	(61)	(170)	(61)
Net assets	$ 69,731	$ 19,470	$ 69,731	$ 19,470

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