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Investments (Tables) | 12 Months Ended
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Dec. 31, 2011
Investments [Abstract] |
Gains And Losses Due To Changes In Fair Value |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (Amounts in thousands) |
Fixed maturity securities |  | $ | 62,149 |  |  | $ | 967 |  |  | $ | 261,866 |
Equity securities |  |  | (30,879 | ) |  |  | 45,659 |  |  |  | 133,580 |
Short-term investments |  |  | 19 |  |  |  | (46 | ) |  |  | 36 |
Total |  | $ | 31,289 |  |  | $ | 46,580 |  |  | $ | 395,482 |
Net Realized Investment Gains |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (Amounts in thousands) |
Net realized gains from investments and other liabilities: |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturities |  | $ | 54,112 |  |  | $ | 5,909 |  |  | $ | 255,195 |
Equity securities |  |  | (4,854 | ) |  |  | 46,547 |  |  |  | 83,452 |
Short-term investments |  |  | 139 |  |  |  | 18 |  |  |  | 76 |
Option and short sale transactions |  |  | 9,000 |  |  |  | 4,615 |  |  |  | 7,721 |
Total |  | $ | 58,397 |  |  | $ | 57,089 |  |  | $ | 346,444 |
Gross Gains And Losses Realized On Sales Of Investments |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (Amounts in thousands) |
|  | Gross Realized Gains |  |  | Gross Realized Losses |  |  | Net |  |  | Gross Realized Gains |  |  | Gross Realized Losses |  |  | Net |  |  | Gross Realized Gains |  |  | Gross Realized Losses |  |  | Net |
Fixed maturities |  | $ | 2,675 |  |  | $ | (10,712 | ) |  | $ | (8,037 | ) |  | $ | 8,754 |  |  | $ | (3,812 | ) |  | $ | 4,942 |  |  | $ | 1,918 |  |  | $ | (8,589 | ) |  | $ | (6,671 | )
Equity securities |  |  | 41,872 |  |  |  | (15,847 | ) |  |  | 26,025 |  |  |  | 16,793 |  |  |  | (15,905 | ) |  |  | 888 |  |  |  | 20,558 |  |  |  | (70,686 | ) |  |  | (50,128 | )
Short-term investments |  |  | 120 |  |  |  | 0 |  |  |  | 120 |  |  |  | 64 |  |  |  | 0 |  |  |  | 64 |  |  |  | 356 |  |  |  | (3,902 | ) |  |  | (3,546 | )
Estimated Fair Values Of Investments |
|  | Estimated Fair Value |
|  | (Amounts in thousands) |
Fixed maturities: |  |  |  |
Due in one year or less |  | $ | 30,756 |
Due after one year through five years |  |  | 370,609 |
Due after five years through ten years |  |  | 556,519 |
Due after ten years |  |  | 1,450,334 |
Mortgage-backed securities |  |  | 37,371 |
Total |  | $ | 2,445,589 |
Investment Income |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
|  | (Amounts in thousands) |
Fixed maturities |  | $ | 130,895 |  |  | $ | 136,345 |  |  | $ | 137,607 |
Equity securities |  |  | 10,869 |  |  |  | 8,435 |  |  |  | 8,558 |
Short-term investments |  |  | 1,747 |  |  |  | 1,413 |  |  |  | 1,082 |
Total investment income |  | $ | 143,511 |  |  | $ | 146,193 |  |  | $ | 147,247 |
Less: Investment expense |  |  | 2,564 |  |  |  | 2,379 |  |  |  | 2,298 |
Net investment income |  | $ | 140,947 |  |  | $ | 143,814 |  |  | $ | 144,949 |

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- Definition Tabular disclosure of the realized and unrealized gains and losses reported in the statement of income which have resulted from the sale and holding of marketable securities, respectively, as well as the sale or disposal of cost method investments. Such amounts would include realized gains and losses on the sale or disposal of trading, available-for-sale, and held-to-maturity securities, unrealized gains and losses on trading securities, unrealized gains and losses on available-for-sale and held-to-maturity securities transferred to the trading securities category, realized gains and losses on the sale or disposal of cost method investments, and losses recognized for other than temporary impairments (OTTI) of such investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (c)-(e) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 5 -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 12 -Subparagraph a, b -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 Accounting Standards Codification -Topic 320 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.M) -URI http://asc.fasb.org/extlink&oid=6784337&loc=d3e87990-122713 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 21 -Subparagraph d -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27405-111563 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section M Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 7, 13, 16, 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. Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6379932&loc=d3e22054-111558 + Details
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