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Investments (Components Of Net Realized Gains, Excluding OTTI Charges) (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2012 | Sep. 30, 2012 | Jun. 30, 2012 | Mar. 31, 2012 | Dec. 31, 2011 | Sep. 30, 2011 | Jun. 30, 2011 | Mar. 31, 2011 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |  |  |
HTM fixed maturity securities gains |  |  |  |  |  |  |  |  | $ 194,000 | $ 4,000 | $ 569,000
HTM fixed maturity securities losses |  |  |  |  |  |  |  |  | (217,000) | (564,000) | (894,000)
Short term investments realized losses |  |  |  |  |  |  |  |  | (2,000) | 0 | 0
Other investments securities gains |  |  |  |  |  |  |  |  | 1,000 | 0 | 0
Other investments securities losses |  |  |  |  |  |  |  |  | (400,000) | 0 | (5,184,000)
Net realized investment gains | 5,540,000 | (1,088,000) | 178,000 | 4,358,000 | (3,621,000) | (2,045,000) | 2,146,000 | 5,760,000 | 13,252,000 | 15,426,000 | 10,575,000
Total OTTI charges recognized in earnings |  |  |  |  |  |  |  |  | (4,264,000) | (13,186,000) | (17,658,000)
Total net realized gains (losses) |  |  |  |  |  |  |  |  | 8,988,000 | 2,240,000 | (7,083,000)
Proceeds from Sale of Available-for-sale Securities |  |  |  |  |  |  |  |  | 205,300,000 | 206,500,000 | 288,500,000
Fixed Maturity Securities [Member] |  |  |  |  |  |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |  |  |
AFS securities gains |  |  |  |  |  |  |  |  | 4,452,000 | 9,385,000 | 8,161,000
AFS securities losses |  |  |  |  |  |  |  |  | (472,000) | (70,000) | (7,619,000)
Equity Securities [Member] |  |  |  |  |  |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |  |  |  |  |  |
AFS securities gains |  |  |  |  |  |  |  |  | 10,901,000 | 6,671,000 | 16,698,000
AFS securities losses |  |  |  |  |  |  |  |  | $ (1,205,000) | $ 0 | $ (1,156,000)

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- Definition The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 16B -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 FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 15D -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 15C -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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