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Investments (OTTI by Asset Type) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
OTTI Losses Gross | $ 43 | $ 342 | $ 4,729 | $ 4,494
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income | (30) | 0 | (36) | 10
OTTI Losses Recognized in Earnings | 73 | 342 | 4,765 | 4,484
AFS Fixed Income Securities [Member] |  |  |  |
OTTI Losses Gross |  |  | 3,179 | 1,175
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  |  | (36) | 10
OTTI Losses Recognized in Earnings |  |  | 3,215 | 1,165
AFS Fixed Income Securities [Member] | US Treasury and Government [Member] |  |  |  |
OTTI Losses Gross |  |  | 31 |
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  |  | 0 |
OTTI Losses Recognized in Earnings |  |  | 31 |
AFS Fixed Income Securities [Member] | Obligations of States and Political Subdivisions [Member] |  |  |  |
OTTI Losses Gross |  |  | 612 |
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  |  | 0 |
OTTI Losses Recognized in Earnings |  |  | 612 |
AFS Fixed Income Securities [Member] | Corporate Securities [Member] |  |  |  |
OTTI Losses Gross | 12 |  | 587 | 1,077
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income | 0 |  | 0 | 0
OTTI Losses Recognized in Earnings | 12 |  | 587 | 1,077
AFS Fixed Income Securities [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |  |  |
OTTI Losses Gross | 11 |  | 96 |
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income | 0 |  | 0 |
OTTI Losses Recognized in Earnings | 11 |  | 96 |
AFS Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member] |  |  |  |
OTTI Losses Gross |  |  | 670 |
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  |  | 0 |
OTTI Losses Recognized in Earnings |  |  | 670 |
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member] |  |  |  |
OTTI Losses Gross | 20 |  | 1,183 | 98
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income | (30) |  | (36) | 10
OTTI Losses Recognized in Earnings | $ 50 |  | 1,219 | 88
Total AFS Securities [Member] | Equity Securities [Member] |  |  |  |
OTTI Losses Gross |  | 342 | 1,360 | 3,319
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  | 0 | 0 | 0
OTTI Losses Recognized in Earnings |  | 342 | 1,360 | 3,319
Other Investments [Member] |  |  |  |
OTTI Losses Gross |  |  | 190 |
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  |  | 0 |
OTTI Losses Recognized in Earnings |  |  | 190 |
Common Stock [Member] | Total AFS Securities [Member] | Equity Securities [Member] |  |  |  |
OTTI Losses Gross |  | 342 | 1,360 | 3,316
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  | 0 | 0 | 0
OTTI Losses Recognized in Earnings |  | $ 342 | $ 1,360 | 3,316
Preferred Stock [Member] | Total AFS Securities [Member] | Equity Securities [Member] |  |  |  |
OTTI Losses Gross |  |  |  | 3
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income |  |  |  | 0
OTTI Losses Recognized in Earnings |  |  |  | $ 3

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- Definition Income Statement line item amount before tax of other than temporary impairment loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity. + References No definition available. + Details
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e25351-111560 + Details
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