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Investments (Components Of Net Realized Gains, Excluding OTTI Charges) (Details) (USD $) | 2 Months Ended | 3 Months Ended | 12 Months Ended
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Mar. 06, 2009 | Dec. 31, 2011 | Sep. 30, 2011 | Jun. 30, 2011 | Mar. 31, 2011 | Dec. 31, 2010 | Sep. 30, 2010 | Jun. 30, 2010 | Mar. 31, 2010 | Jun. 30, 2009 securities | Mar. 31, 2009 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
HTM fixed maturity securities Gains |  |  |  |  |  |  |  |  |  |  |  | $ 4,000 | $ 569,000 | $ 225,000
HTM fixed maturity securities Losses |  |  |  |  |  |  |  |  |  | (200,000) |  | (564,000) | (894,000) | (1,049,000)
AFS fixed maturity securities Gains |  |  |  |  |  |  |  |  |  |  |  | 9,385,000 | 8,161,000 | 20,899,000
AFS fixed maturity securities Losses |  |  |  |  |  |  |  |  |  |  |  | (70,000) | (7,619,000) | (13,889,000)
AFS equity securities Gains |  |  |  |  |  |  |  |  |  | 7,700,000 | 19,700,000 | 6,671,000 | 16,698,000 | 33,355,000
AFS equity securities Losses |  |  |  |  |  |  |  |  |  | (8,300,000) | 19,100,000 | 0 | (1,156,000) | (28,056,000)
Other investments Gains |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 | 0
Other investments Losses |  |  |  |  |  |  |  |  |  |  |  | 0 | (5,184,000) | (2,039,000)
Total other net realized investment gains |  | (3,621,000) | (2,045,000) | 2,146,000 | 5,760,000 | (3,812,000) | 57,000 | (3,264,000) | (64,000) |  |  | 15,426,000 | 10,575,000 | 9,446,000
Total OTTI charges recognized in earnings |  |  |  |  |  |  |  |  |  |  |  | (13,186,000) | (17,658,000) | (55,416,000)
Total net realized gains (losses) |  |  |  |  |  |  |  |  |  |  |  | 2,240,000 | (7,083,000) | (45,970,000)
Proceeds From Sale Of Available For Sale Securities |  |  |  |  |  |  |  |  |  |  |  | 206,500,000 | 288,500,000 | 676,000,000
Sale of equity securities, available-for-sale |  |  |  |  |  |  |  |  |  |  |  | 60,071,000 | 98,015,000 | 137,244,000
Available For Sale Securities Net Realized Gains |  |  |  |  |  |  |  |  |  | (600,000) | (600,000) |  |  |
Overall Market Decline | 24.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Decrease Increase In The Parent Market Capitalization | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Equity securities, AFS |  | 157,355,000 |  |  |  | 69,636,000 |  |  |  | 31,100,000 |  | 157,355,000 | 69,636,000 |
Number Of Held To Maturity Securities Sold During The Period |  |  |  |  |  |  |  |  |  | 1 |  |  |  |
Held-to-maturity Securities, Sold Security, at Carrying Value |  |  |  |  |  |  |  |  |  | 6,000,000 |  |  |  |
Equity Securities [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total OTTI charges recognized in earnings |  |  |  |  |  |  |  |  |  |  |  | $ (11,365,000) | $ (2,543,000) | $ (2,107,000)

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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 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. Reference 4: 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. + Details
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