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Segment Information (Income From Continuing Operations, Before Federal Income Tax) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013
Segment Reporting Information [Line Items] |  |  |  |
Net investment income earned | $ 36,774 | $ 34,003 | $ 72,308 | $ 66,873
Net realized investment gains | 4,539 | 5,154 | 11,757 | 8,509
Total investment revenues | 41,313 | 39,157 | 84,065 | 75,382
Tax on investment income | 10,941 | 10,107 | 22,516 | 19,312
Total Investment Income After Federal Income Tax | 30,372 | 29,050 | 61,549 | 56,070
Total Standard Commercial Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | 15,703 | 9,743 | 12,073 | 15,845
Total Standard Personal Lines [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | (5,582) | (2,975) | (7,942) | 2,998
Total Standard Insurance Operations [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | 10,121 | 6,768 | 4,131 | 18,843
GAAP combined ratio | 97.60% | 98.30% | 99.50% | 97.60%
Statutory combined ratio | 97.30% | 97.00% | 99.20% | 96.90%
Excess And Surplus Operations [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Underwriting gain (loss), before federal income tax | $ (37) | $ (2,285) | $ 938 | $ (2,199)
GAAP combined ratio | 100.10% | 107.60% | 98.60% | 103.70%
Statutory combined ratio | 99.90% | 106.80% | 98.80% | 102.60%

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- Definition The income earned from investments in securities and other investments including dividends, interest, and returns on other investments. This item does not include realized gains (losses). + References No definition available. + Details
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- Definition The statutory combined ratio (expressed as a percentage) is the sum of: (i) the loss and loss expense ratio; (ii) the underwriting ratio; and (iii) the dividend ratio. The loss and loss expense ratio as well as the dividend ratio is calculated by dividing loss and loss expenses, as well as dividends to policyholders, by net premiums earned. The underwriting expense ratio is calculated by dividing underwriting expenses by net premiums written. + References No definition available. + Details
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- Definition Taxes paid on investment income + References No definition available. + Details
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- Definition The income earned from investments in securities and other investments including dividends, interest, and returns on other investments, including realized gains/losses, after-tax + References No definition available. + Details
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- Definition The income earned from investments in securities and other investments including dividends, interest, and returns on other investments, including realized gains/losses. + References No definition available. + Details
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- Definition Net premiums earned and other insurance income less net loss and loss expenses incurred, loss adjustment expenses, policy acquisition costs and other underwriting expenses. + References No definition available. + Details
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- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3(a)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 325 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6485959&loc=d3e22529-158502 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 3 -Subparagraph a -Article 7 + Details
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