Fair Value Measurements (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2010	Jun. 30, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Independent pricing services to assist in determining fair value		99.00%
Gain recognized on termination of interest in insurance contract	$ 8.0

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