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Investment Securities (Significant Unobservable Inputs) (Details) (USD $) |  | 12 Months Ended |
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Dec. 31, 2013 Investment | Dec. 31, 2013 Standard & Poor's, AA+ Rating [Member] Agency CMBS Broker Pricing | Dec. 31, 2013 Standard Poors NR Rating [Member] Redeemable preferred stocks Discounted cash flows | Dec. 31, 2013 Standard Poors NR Rating [Member] Redeemable preferred stocks Discount Yield | Dec. 31, 2012 Standard Poors NR Rating [Member] Redeemable preferred stocks Multiple of GAAP book value | Dec. 31, 2013 Standard Poors NR Rating [Member] Private equity funds Multiple of GAAP book value | Dec. 31, 2013 Standard Poors NR Rating [Member] Private equity funds Market Approach Valuation Technique [Member] | Dec. 31, 2013 Standard Poors NR Rating [Member] Private equity securities Market Approach Valuation Technique [Member]
Quantitative information for Level 3 Fair Value Measurements Assets |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value Assets |  | $ 22,000,000 | [1],[2] | $ 71,000,000 | [2] |  |  | $ 35,600,000 | [2] | $ 10,500,000 | [2] | $ 6,100,000 | [2]
Share Price of Recent Transaction Used As Unobservable Input |  |  |  |  |  |  |  |  |  |  |  | 6.1 |
Average Share Price Used As Unobservable Input |  |  |  |  |  |  |  |  |  | $ 1.10 |  |  |
Book Value Multiple to Calculate Fair Value |  |  |  |  |  |  | 100.00% |  |  |  |  |  |
Discount Yield (as a percent) |  |  |  |  |  | 7.40% |  |  |  |  |  |  |
Number of Investments with Significant Unobseravble Inputs | 1 |  |  |  |  |  |  |  |  |  |  |  |
[1] | As of December 31, 2013 each asset type consists of one security.
[2] | Credit ratings are assigned based on the following hierarchy: 1) Standard & Poor’s and 2) Moody’s.

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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 Average Share Price Used As Unobservable Input + References No definition available. + Details
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- Definition Book Value Multiple to Calculate Fair Value + References No definition available. + Details
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- Definition Number of Investments with Significant Unobseravble Inputs + 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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