Investments in Unconsolidated Companies (Schedule of Long-term Debt Maturities) (Details) (Equity Method Investments [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
2012	$ 30,285
2013	97,601
2014	44,871
2015	64,319
2016	14,948
Thereafter	156,484
Long-term debt, total	$ 408,508

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