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Federal Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Change in Net Deferred Federal Income Tax Assets | $ 52,900 |  |
Net loss reserve discounting | 38,771 | $ 70,065 |
Net unearned premiums | 50,267 | 78,201 |
Employee benefits | 8,606 | 17,881 |
Long-term incentive compensation plans | 12,221 | 17,750 |
Temporary investment write-downs | 1,044 | 2,475 |
Other investment-related items, net | 0 | 1,484 |
Net operating loss | 54 | 771 |
Other | 5,784 | 8,344 |
Total deferred tax assets | 116,747 | 196,971 |
Deferred policy acquisition costs | 47,484 | 75,310 |
Unrealized gains on investment securities | 26,183 | 22,681 |
Other investment-related items, net | 2,500 | 0 |
Accelerated depreciation and amortization | 8,590 | 14,140 |
Total deferred tax liabilities | 84,757 | 112,131 |
Tax benefits related to compensation expense deductions for share-based compensation awards | 23,800 | $ 23,800 | $ 22,000
Investments [Member] |  |  |
Change in Net Deferred Federal Income Tax Assets | $ 21,400 |  |

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- Definition The tax effect as of the balance sheet date of the amount of the estimated future tax deductions, before any related valuation allowance, arising from unrealized losses on securities which can only be deducted for tax purposes when the losses are realized, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken. + References No definition available. + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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