General Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of total interest cost to interest expense
Total interest cost including amortization of debt issuance costs	$ 84,349	$ 90,698	$ 49,610
Capitalized interest	(11,212)
Total interest expense as reported	$ 73,137	$ 90,698	$ 49,610