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Federal Income Taxes (Reconciliation of Federal Income Tax on Income at the Corporate Rate to the Effective Tax Rate) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Provisional Increase to Deferred Tax Asset | $ 7,500 |  |
Tax at statutory rate of 35% | 91,689 | $ 76,984 | $ 81,442
Tax-advantaged interest | (11,510) | (12,126) | (13,164)
Dividends received deduction | (1,961) | (1,114) | (1,817)
Share-based compensation expense income tax benefit | (4,281) | 0 | 0
Tax Reform Deferred Tax Asset Impact | 20,205 | 0 | 0
Tax Benefit on Unrealized Gains | 5,700 |  |
Other | (1,000) | (2,284) | 370
Total federal income tax expense | $ 93,142 | $ 61,460 | $ 66,831

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- Definition The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to investment income that is tax advantaged. Tax advantaged investment securities generally are, by statute, tax-reduced, tax-deferred, or tax-free. + References No definition available. + Details
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- Definition Provisional Increase to Deferred Tax Asset due to the change in approach from the Tax Cuts and Jobs Act. + References No definition available. + Details
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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