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Long-term Debt (Details Textual) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2012 | Jun. 30, 2011 | Jun. 30, 2012 | Jun. 30, 2011 | Aug. 15, 2012
Long-term Debt (Textual) [Abstract] |  |  |  |  |
Total par value of repurchased surplus notes | $ 789,179 |  | $ 789,179 |  |
Aggregate cash payment | 188,446 |  | 188,446 |  | 188,000
Losses (gains) on extinguishment of debt | 177,745 | (3,119) | 177,745 | (3,119) |
5.1% surplus notes, general account, due 2020 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Percentage of debt instrument | 5.10% |  | 5.10% |  |
Aggregate par value of surplus notes subject to call options | $ 939,179 |  | $ 939,179 |  |
5.1% surplus notes, segregated account, due 2020 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Percentage of debt instrument | 5.10% |  | 5.10% |  |
5.1% junior surplus notes, segregated account, due 2020 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Percentage of debt instrument | 5.10% |  | 5.10% |  |

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- Definition Aggregate par value of surplus notes subject to call option agreements. + References No definition available. + Details
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- Definition Aggregate payment to repurchase surplus notes. + References No definition available. + Details
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- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Face (par) amount of the original debt instrument that was repurchased. + References No definition available. + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 26 -Paragraph 20, 21 -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 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629 + Details
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