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Adoption of Accounting Pronouncements (Balance Sheet Information) (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2012 | Dec. 31, 2011
Deferred policy acquisition costs | $ 161,505,000 | $ 135,761,000 |
Deferred federal income tax recoverable | 91,916,000 | 119,486,000 | [1]
Retained earnings | 1,131,115,000 | 1,116,319,000 |
Adjustment of deferred tax assets | 600,000 | 600,000 |
As Previously Reported [Member] |  |  |
Deferred policy acquisition costs |  | 214,069,000 |
Deferred federal income tax recoverable |  | 92,078,000 | [1]
Retained earnings |  | 1,167,219,000 |
Add: Adjustment for the cumulative effect on prior years of applying retroactively the new method of accounting for deferred policy acquisition costs [Member] |  |  |
Deferred policy acquisition costs |  | (78,308,000) |
Deferred federal income tax recoverable |  | 27,408,000 | [1]
Retained earnings |  | $ (50,900,000) |
[1] | 1 Included in the deferred federal income tax recoverable amount is an adjustment of $0.6 million reflecting the revaluation of a deferred tax asset acquired as part of the purchase of Mesa Underwriters Specialty Insurance Company ("MUSIC" ). For additional information, see Footnote 14, "Federal Income Taxes"

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- Definition The acquisition revaluation decrease of the sum of the tax effects as of the balance sheet date of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset. + References No definition available. + Details
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- Definition Net amount of deferred policy acquisition costs capitalized on contracts remaining in force as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 28, 29, 30, 31 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 60 -Subparagraph c -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 AICPA -Name Statement of Position (SOP) -Number 95-1 -Paragraph 19-23 -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 944 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6481648&loc=d3e11198-158413 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 120 -Paragraph 5, 6 -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 SEC -Name Regulation S-X (SX) -Number 210 -Section 16 -Article 12 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 97 -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. Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 825 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6487548&loc=d3e32546-158582 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 7 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),7) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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