Fair Value Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Trust Preferred - Real Estate Investment Trusts [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed		0.00%
Trust Preferred - Real Estate Investment Trusts [Member] | Constant Default Rate Year 4 to 6 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		1.00%
Trust Preferred - Real Estate Investment Trusts [Member] | Constant Default Rate Years 7 to Maturity [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		0.50%
Trust Preferred - Predominantly Insurance [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed		5.00%
Trust Preferred - Predominantly Banks [Member] | Constant Default Rate 2016 to Maturity [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed	3.00%	3.00%
Minimum [Member] | Other Predominantly ABS CODs [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		0.01%
Discount rate range of LIBOR utilized for fair value purposes		9.00%
Minimum [Member] | Trust Preferred - Real Estate Investment Trusts [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Discount rate range of LIBOR utilized for fair value purposes		5.50%
Minimum [Member] | Trust Preferred - Real Estate Investment Trusts [Member] | Constant Default Rate Year 1 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		4.10%
Minimum [Member] | Trust Preferred - Real Estate Investment Trusts [Member] | Constant Default Rate Year 2 to 3 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		4.60%
Minimum [Member] | Trust Preferred - Individual Banks [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Significant Unobservable Inputs, Yield Rate		6.60%
Significant Unobservable Inputs, Price Rate		81.25%
Minimum [Member] | Trust Preferred - Predominantly Insurance [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Significant Unobservable Inputs, Loss Given Deferral Rate		2.18%
Discount rate range of LIBOR utilized for fair value purposes		3.72%
Minimum [Member] | Trust Preferred - Predominantly Insurance [Member] | Constant Default Rate Year 1 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		0.38%
Minimum [Member] | Trust Preferred - Predominantly Insurance [Member] | Constant Default Rate Year 2 to 5 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		0.53%
Minimum [Member] | Trust Preferred - Predominantly Insurance [Member] | Constant Default Rate Year 6 to Maturity [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		0.50%
Minimum [Member] | Trust Preferred - Predominantly Banks [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Significant Unobservable Inputs, Loss Given Deferral Rate	8.17%	14.39%
Discount rate range of LIBOR utilized for fair value purposes	5.10%	5.60%
Minimum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Until 2016 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed	5.50%	5.50%
Minimum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Year 1 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate	0.30%	0.30%
Minimum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Year 2 to 5 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate	0.48%	0.49%
Minimum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Year 6 to Maturity [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate	0.59%	0.58%
Maximum [Member] | Other Predominantly ABS CODs [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		100.00%
Discount rate range of LIBOR utilized for fair value purposes		22.00%
Maximum [Member] | Trust Preferred - Real Estate Investment Trusts [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Discount rate range of LIBOR utilized for fair value purposes		15.00%
Maximum [Member] | Trust Preferred - Real Estate Investment Trusts [Member] | Constant Default Rate Year 1 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		10.60%
Maximum [Member] | Trust Preferred - Real Estate Investment Trusts [Member] | Constant Default Rate Year 2 to 3 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		5.50%
Maximum [Member] | Trust Preferred - Individual Banks [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Significant Unobservable Inputs, Yield Rate		7.80%
Significant Unobservable Inputs, Price Rate		109.60%
Maximum [Member] | Trust Preferred - Predominantly Insurance [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Significant Unobservable Inputs, Loss Given Deferral Rate		30.13%
Discount rate range of LIBOR utilized for fair value purposes		6.49%
Maximum [Member] | Trust Preferred - Predominantly Insurance [Member] | Constant Default Rate Year 1 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		1.03%
Maximum [Member] | Trust Preferred - Predominantly Insurance [Member] | Constant Default Rate Year 2 to 5 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		0.89%
Maximum [Member] | Trust Preferred - Predominantly Insurance [Member] | Constant Default Rate Year 6 to Maturity [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate		0.55%
Maximum [Member] | Trust Preferred - Predominantly Banks [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Significant Unobservable Inputs, Loss Given Deferral Rate	100.00%	100.00%
Discount rate range of LIBOR utilized for fair value purposes	5.70%	7.70%
Maximum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Until 2016 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed	26.19%	20.73%
Maximum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Year 1 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate	2.75%	1.94%
Maximum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Year 2 to 5 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate	0.87%	1.14%
Maximum [Member] | Trust Preferred - Predominantly Banks [Member] | Constant Default Rate Year 6 to Maturity [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption For Fair Value Of Assets Or Liabilities Constant Default Rate	0.65%	0.65%
Asset-Backed Securities [Member] | Trust Preferred - Predominantly Insurance [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Static Pool Losses		100.00%
Asset-Backed Securities [Member] | Trust Preferred - Predominantly Banks [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Static Pool Losses	100.00%	100.00%
Asset-Backed Securities [Member] | Minimum [Member] | Other Predominantly ABS CODs [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Static Pool Losses		70.00%
Asset-Backed Securities [Member] | Minimum [Member] | Trust Preferred Securities - Real Estate Investment Trusts [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Static Pool Losses		60.00%
Asset-Backed Securities [Member] | Maximum [Member] | Other Predominantly ABS CODs [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Static Pool Losses		92.00%
Asset-Backed Securities [Member] | Maximum [Member] | Trust Preferred Securities - Real Estate Investment Trusts [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Static Pool Losses		100.00%
Level 3 [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Investments, Fair Value Disclosure	$ 702,449	$ 1,304,877
Level 3 [Member] | Other Predominantly ABS CODs [Member] | Asset-Backed Securities [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Investments, Fair Value Disclosure		25,800
Level 3 [Member] | Trust Preferred - Predominantly Insurance [Member] | Asset-Backed Securities [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Investments, Fair Value Disclosure		346,390
Level 3 [Member] | Trust Preferred - Predominantly Banks [Member] | Asset-Backed Securities [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Investments, Fair Value Disclosure	740,261	921,819
Level 3 [Member] | Trust Preferred - Individual Banks [Member] | Asset-Backed Securities [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Investments, Fair Value Disclosure		22,324
Level 3 [Member] | Trust Preferred - Real Estate Investment Trusts [Member] | Asset-Backed Securities [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Investments, Fair Value Disclosure	0	22,996
Level 3 [Member] | Other Credit Derivatives [Member] | Asset-Backed Securities [Member]
Summary of Quantitative Information Relating to the Principal Valuation Techniques and Significant Unobservable Inputs for Level 3 [Line Items]
Investments, Fair Value Disclosure	$ 28