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Investments (OTTI by Asset Type) (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
OTTI Losses Gross | $ 11,998 | $ 16,225 | $ 64,184
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | (1,188) | (1,433) | 8,768
OTTI Losses Recognized in Earnings | 13,186 | 17,658 | 55,416
Equity Securities [Member] |  |  |
OTTI Losses Gross | 11,365 | 2,543 | 2,107
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | 0 | 0 | 0
OTTI Losses Recognized in Earnings | 11,365 | 2,543 | 2,107
Residential Mortgage Backed Securities ("RMBS") [Member] |  |  |
Number of Impairments due to intent to sell |  | 2 |
Fixed Maturity Securities [Member] |  |  |
OTTI Losses Gross | 633 | 13,682 | 62,077
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | (1,188) | (1,433) | 8,768
OTTI Losses Recognized in Earnings | 1,821 | 15,115 | 53,309
Fixed Maturity Securities [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
OTTI Losses Gross | 17 | 197 |
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | 0 | 0 |
OTTI Losses Recognized in Earnings | 17 | 197 |
Fixed Maturity Securities [Member] | Corporate Securities [Member] |  |  |
OTTI Losses Gross | 244 |  | 1,271
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | 0 |  | 0
OTTI Losses Recognized in Earnings | 244 |  | 1,271
Fixed Maturity Securities [Member] | Asset-backed Securities ("ABS") [Member] |  |  |
OTTI Losses Gross | 175 | (20) | 1,190
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | (546) | (179) | (1,292)
OTTI Losses Recognized in Earnings | 721 | 159 | 2,482
Fixed Maturity Securities [Member] | Commercial Mortgage-backed Securities ("CMBS") [Member] |  |  |
OTTI Losses Gross | (149) | 5,552 | 18,865
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | (843) | (863) | 7,088
OTTI Losses Recognized in Earnings | 694 | 6,415 | 11,777
Average unrealized unrecognized loss as compared to amortized cost percentage |  | 60.00% |
Decline In Fair Value As Compared To Amortized Cost |  |  | 77.00%
Conditional Default Rates Range Low End Of Range |  |  | 2.5
Conditional Default Rates Range High End Of Range |  |  | 3.0
Fixed Maturity Securities [Member] | Residential Mortgage Backed Securities ("RMBS") [Member] |  |  |
OTTI Losses Gross | 346 | 7,953 | 40,751
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income | 201 | (391) | 2,972
OTTI Losses Recognized in Earnings | 145 | 8,344 | 37,779
Decline In Fair Value As Compared To Amortized Cost |  |  | 65.00%
Conditional Default Rates |  |  | 0.33
Securities In Loss Position With Intent to Sell [Member] | Equity Securities [Member] |  |  |
OTTI Losses Recognized in Earnings | 2,900 |  |
Securities Which Will Not Recover In The Near Term [Member] | Equity Securities [Member] |  |  |
OTTI Losses Recognized in Earnings | $ 8,500 |  |

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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 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 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 16 -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 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 5: 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=6943989&loc=d3e3602-108585 Reference 6: 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=6956420&loc=d3e25351-111560 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-2/124-2 -Paragraph 22 -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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- 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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