Investments in Unconsolidated Affiliates (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Assets:
Current assets	$ 40,349		$ 40,349
Noncurrent assets	163,743		163,743
Total assets	204,092		204,092
Liabilities:
Current liabilities	40,792		40,792
Noncurrent liabilities	86,424		86,424
Total liabilities	127,216		127,216
Results of operations:
Revenue	31,403	45,934	54,187	68,942
Net loss	$ (5,328)	$ 6	$ (13,697)	$ (7,735)