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Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Income Taxes |  |  |
Income tax expense differences from the amount computed by applying the U.S. Federal income tax rate to income before income taxes (as a percent) | 35.00% | 35.00% | 35.00%
Reasons for the difference of income tax expense |  |  |
Computed expected tax expense | $ 64,183 | $ 55,634 | $ 66,941
Change in taxes resulting from: |  |  |
Tax-exempt interest income | (4,828) | (4,381) | (3,682)
State tax, net of federal income taxes and tax credit | (110) | 1,446 | 3,302
Tax refunds | (966) |  |
Other investment income | (2,656) | (2,691) | (3,083)
Other | 616 | 557 | 600
Total income taxes | $ 56,239 | $ 50,565 | $ 64,078

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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319 + Details
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