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Federal Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | --- | ---
Net loss reserve discounting | $ 74,436 | $ 84,502 |
Net unearned premiums | 72,057 | 66,470 |
Employee benefits | 30,432 | 33,721 |
Long-term incentive compensation plans | 15,551 | 13,625 |
Temporary investment write-downs | 5,419 | 3,939 |
Net operating loss | 1,454 | 2,136 |
Alternative minimum tax credits | 0 | 7,400 |
Other | 8,132 | 9,237 |
Total deferred tax assets | 207,481 | 221,030 |
Deferred policy acquisition costs | 72,481 | 63,242 |
Unrealized gains on investment securities | 24,228 | 43,289 |
Other investment-related items, net | 5,566 | 5,088 |
Accelerated depreciation and amortization | 12,510 | 10,962 |
Total deferred tax liabilities | 114,785 | 122,581 |
Net deferred federal income tax asset | 92,696 | 98,449 |
Tax benefits related to compensation expense deductions for share-based compensation awards | $ 22,000 | $ 20,200 | $ 19,200

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