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Investment Securities (Significant Unobservable Inputs) (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2014 | Dec. 31, 2013
NR | Preferred Stock | Discounted cash flows |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair value Assets | $ 71,300,000 | $ 71,000,000
NR | Preferred Stock | Discount Yield [Member] |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Discount Yield (as a percent) | 6.90% | 7.40%
NR | Private equity funds | Multiple of GAAP book value |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair value Assets | 36,400,000 | 35,600,000
Book value multiple (as a percent) | 100.00% | 100.00%
NR | Private equity funds | Average Share Price [Member] |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Average Share Price Used As Unobservable Input | 1.10 | 1.10
NR | Private equity funds | Recent transaction [Member] |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair value Assets | 10,500,000 | 10,500,000
NR | Convertible Preferred Stock [Member] | Recent transaction [Member] |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair value Assets | 6,100,000 | 6,100,000
Share Price of Recent Transaction Used As Unobservable Input | 6.1 | 6.1
AAA | Non-Agency Commercial Mortgage Backed Securities [Member] [Member] | Broker Indication [Member] |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair value Assets | 13,300,000 |
Fair value input, swap spread rate | 0.80% |
AA | Mortgage-backed and asset-backed securities | Broker Pricing |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair value Assets | 22,000,000 | 22,000,000
Standard & Poor's, BBB- Rating [Member] | Non-Agency Commercial Mortgage Backed Securities [Member] [Member] | Broker Pricing |  |
Quantitative information for Level 3 Fair Value Measurements Assets |  |
Fair value Assets | $ 6,300,000 |

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Book Value Multiple to Calculate Fair Value + References No definition available. + Details
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- Definition Represents the swap spread input used to measure fair value. + References No definition available. + Details
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- Definition Share Price of Recent Transaction Used As Unobservable Input + References No definition available. + Details
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