Basis of Presentation and Significant Accounting Policies (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Excise and Sales Taxes	$ 6,400,000	$ 28,900,000	$ 27,300,000	$ 89,700,000
Restricted Cash and Investments [Abstract]
Restricted Cash and Investments, Current	3,600,000		3,600,000		3,600,000
Restricted Cash and Investments, Noncurrent	$ 8,700,000		$ 8,700,000		$ 7,800,000