Fair Value Measurements - Quantitative Information for Level Three Inputs (Details) (Market Yield [Member], Fair Value, Inputs, Level 3 [Member], USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Senior Debt [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	142.5
Senior Debt [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.20%
Senior Debt [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	17.00%
Senior Debt [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	6.60%
Junior Debt [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	147.9
Junior Debt [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	9.00%
Junior Debt [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	25.10%
Junior Debt [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	14.80%