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Fair Value of Financial Instruments - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Fair Value of Financial Instruments (Textual) [Abstract] |  |  |  |
Realized loss on impairment of securities |  |  | $ 1,874 |
Level 3 |  |  |  |
Fair Value of Financial Instruments (Textual) [Abstract] |  |  |  |
Percentage of invested assets in total investment portfolio Level 3 recurring | 3.30% |  | 3.30% |
Net realized investment losses | $ 2,587 | $ 68 | $ 6,133 | $ 2,066

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- Definition Fair value of financial instruments. + References No definition available. + Details
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- Definition Percentage of invested assets in the total investment portfolio in Level 3 carried at fair value on a recurring basis. + References No definition available. + Details
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- Definition Amount of loss realized on the sale of debt or equity securities classified as available-for-sale. Excludes other than temporary impairments (OTTI). + References No definition available. + Details
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- Definition Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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