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Stockholders' Equity and Comprehensive Income (Reclassification out of AOCI) (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Total HTM Related, Tax | $ (552) | $ (851) | $ (799)
Amount reclassified from AOCI, HTM | (1,025) | (1,581) | (1,484)
Total realized gains and losses on AFS disposals, gross | (23,540) | (9,412) | (2,801)
Realized gains and losses on AFS disposals, Tax | 8,239 | 3,294 | 980
Realized gains on available for sale securities | (15,301) | (6,118) | (1,821)
Amount reclassified into Net Income: Net actuarial loss, Gross | 4,374 | 5,903 | 4,172
Prior service cost | 10 | 150 | 150
Curtailment Expense | 16 |  |
Total defined benefit pension and post-retirement life, Gross | 64,054 | (20,513) | (12,477)
Total defined benefit pension and post-retirement life,Tax | 22,419 | (7,179) | (4,367)
Total defined benefit pension and post-retirement plans | 41,635 | (13,334) | (8,110)
Other-than-Temporary Impairment [Member] |  |  |
Amount reclassified from AOCI | 9 | 182 | 321
Policy acquisition costs [Member] |  |  |
Amount reclassified into Net Income: Net actuarial loss, Gross | 3,465 |  |
Prior service cost | 3 |  |
Curtailment Expense | 16 |  |
Loss and loss expense incurred [Member] |  |  |
Amount reclassified into Net Income: Net actuarial loss, Gross | 909 |  |
Prior service cost | 7 |  |
Net Realized Investment Gains [Member] |  |  |
Unrealized gains and losses on HTM disposals | 390 |  |
Total realized gains and losses on AFS disposals, gross | (23,540) |  |
Net Income Financial Statement Line Item [Member] |  |  |
Amount reclassified from AOCI | (13,457) |  |
Amount reclassified from AOCI, HTM | (1,025) |  |
Realized gains on available for sale securities | (15,301) |  |
Net Income Financial Statement Line Item [Member] | Accumulated Defined Benefit Plans Adjustment [Member] |  |  |
Total defined benefit pension and post-retirement plans | 2,860 |  |
Net Income Financial Statement Line Item [Member] | Other-than-Temporary Impairment [Member] |  |  |
Amount reclassified from AOCI | 9 |  |
Total Federal Income Tax Expense [Member] |  |  |
Total HTM Related, Tax | (552) |  |
Realized gains and losses on AFS disposals, Tax | 8,239 |  |
Total defined benefit pension and post-retirement life,Tax | (1,540) |  |
Total Federal Income Tax Expense [Member] | Other-than-Temporary Impairment [Member] |  |  |
Amortization of non-credit OTTI losses on HTM securities, tax | (5) |  |
Income From Continuing Operations Before Federal Income Tax [Member] |  |  |
Amortization on net unrealized gains on HTM securities | (1,577) |  |
Total realized gains and losses on AFS disposals, gross | (23,540) |  |
Amount reclassified into Net Income: Net actuarial loss, Gross | 4,374 |  |
Prior service cost | 10 |  |
Curtailment Expense | 16 |  |
Total defined benefit pension and post-retirement life, Gross | 4,400 |  |
Net Investment Income Earned [Member] |  |  |
Amortization on net unrealized gains on HTM securities | (1,967) |  |
Net Investment Income Earned [Member] | Other-than-Temporary Impairment [Member] |  |  |
Amortization of non-credit OTTI losses on HTM securities | $ 14 |  |

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