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Investments (Number of Securities in an Unrealized Unrecognized Loss Position) (Details) (USD $) | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | ---
Number of securities in an unrealized/unrecognized loss position | 141 |  |  |
Unrealized Unrecognized Loss | $ 10,635,000 |  | $ 21,557,000 |
Aggregate unrealized loss position | 5,747,000 | [1] | 11,572,000 | [1]
Securities In Unrealized Unrecognized Loss Position For More Than Twelve Months Unrealized Unrecognized Loss | 4,900,000 |  | 8,600,000 |
Non-Credit OTTI Charges | 2,100,000 |  |  |
Decline in fair value percentage | 6.00% |  |  |
Eighty Percent to Ninety-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | 140 |  | 193 |
Unrealized Unrecognized Loss | 10,166,000 |  | 16,310,000 |
Sixty Percent to Seventy-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | 0 |  | 2 |
Unrealized Unrecognized Loss | 0 |  | 1,125,000 |
Forty Percent to Fifty-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | 1 |  | 2 |
Unrealized Unrecognized Loss | 469,000 |  | 2,160,000 |
Twenty Percent to Thirty-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | 0 |  | 1 |
Unrealized Unrecognized Loss | 0 |  | 986,000 |
Zero Percent to Nineteen Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | 0 |  | 1 |
Unrealized Unrecognized Loss | 0 |  | 976,000 |
Commercial Mortgage-backed Securities ("CMBS") [Member] |  |  |  |
Securities In Unrealized Unrecognized Loss Position For More Than Twelve Months Unrealized Unrecognized Loss |  |  | 5,800,000 |
Commercial Mortgage-backed Securities ("CMBS") [Member] | Previously Impaired Securities With Further Impairment [Member] |  |  |  |
Securities In Unrealized Unrecognized Loss Position For More Than Twelve Months Unrealized Unrecognized Loss |  |  | 3,700,000 |
Commercial Mortgage-backed Securities ("CMBS") [Member] | Unrealized Unrecognized Losses On Securities Without Non Credit Impairment [Member] |  |  |  |
Securities In Unrealized Unrecognized Loss Position For More Than Twelve Months Unrealized Unrecognized Loss |  |  | 2,100,000 |
Decline in fair value percentage |  |  | 17.00% |
Residential Mortgage Backed Securities And Asset Backed Securities [Member] |  |  |  |
Decline in fair value percentage |  |  | 5.00% |
Number of securities in an unrealized/unrecognized loss position for more than twelve months |  |  | 16 |
Equity Securities [Member] |  |  |  |
Aggregate unrealized loss position | 88,000 | [1] | 0 | [1]
Municipal Securities, Residential Mortgage Backed Securities, and Asset Backed Securities [Member] |  |  |  |
Securities In Unrealized Unrecognized Loss Position For More Than Twelve Months Unrealized Unrecognized Loss |  |  | $ 2,800,000 |
Number of securities in an unrealized/unrecognized loss position for more than twelve months |  |  | 37 |
Obligations of States and Political Subdivisions [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position for more than twelve months |  |  | 21 |
[1] | Gross unrealized losses include non-OTTI unrealized amounts and OTTI losses recognized in AOCI. In addition, this column includes remaining unrealized gain or loss amounts on securities that were transferred to an HTM designation in the first quarter of 2009 for those securities that are in a net unrealized/unrecognized loss position.

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- Definition Non-credit portion of other-than-temporary impairment losses on fixed maturity securities recognized in other comprehensive income that have been in a loss position for more than twelve months. This item includes subsequent changes to these securities such as amortization on HTM securities or subsequent sales. This item does not include subsequent changes in appreciation or loss in value. + References No definition available. + Details
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- Definition This item contains disclosure of the number of available-for-sale and held-to-maturity securities determined to be in an unrealized/unrecognized loss position. + References No definition available. + Details
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- Definition This item represents the percentage decline in fair value of fixed maturity securities compared to amortized cost that have been in a loss position for more than twelve months. This impairment has been determined to be temporary. + References No definition available. + Details
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- Definition Represents total unrealized and unrecognized losses of all available-for-sale and held-to-maturity securities in an unrealized and unrecognized loss position for more than 12 months as of the end of the period. + References No definition available. + Details
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- Definition This item contains disclosure of the number of securities determined to be in an unrealized/unrecognized loss position for more than twelve months. + References No definition available. + Details
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- Definition This item represents the sum of (i) the excess of amortized cost over fair value for available-for-sale securities that are in a loss position and (ii) the market fluctuations on held-to-maturity securities from the later of (a) the date a security is designated as held-to-maturity; or (b) the date that an other-than-temporary impairment charge is recognized on a held-to-maturity security for securities that are in an unrecognized loss position. + References No definition available. + Details
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- Definition This item represents the excess of amortized cost basis over fair value of securities that have been in a loss position for less than twelve months for those securities which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 17 -Subparagraph a -Clause 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 03-1 -Paragraph 21 -Subparagraph a -Clause 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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