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Statutory Accounting and Regulatory Requirements (Details Textual) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Statutory Accounting and Regulatory Requirements (Textual) [Abstract] |  |  |
Dividends to the Company | 10.00% |  |
Dividends paid | $ 21.0 | $ 32.0 | $ 32.3
Dividends paid without seeking regulatory approval | $ 32.4 |  |

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- Definition Statutory accounting practices future dividend payments percentage. + References No definition available. + Details
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- Definition Amount of dividends distributed to shareholders in the current accounting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 50 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6483535&loc=d3e16392-158451 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 60 -Subparagraph h(3) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Amount available as of the balance sheet date for dividend payments after computation of statutory restrictions on capital surplus. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 60 -Subparagraph h -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 944 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529 + Details
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