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Income Taxes (Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Deferred tax assets: |  |
20% of net unearned premiums | $ 52,644 | $ 47,110
Discounting of loss reserves and salvage and subrogation recoverable for tax purposes | 9,245 | 6,451
Write-down of impaired investments | 356 | 387
Tax credit carryforwards | 0 | 230
Expense accruals | 7,019 | 6,192
Tax asset on net unrealized loss on securities carried at fair value | 1,055 | 0
Other deferred tax assets | 3,257 | 3,174
Total gross deferred tax assets | 73,576 | 63,544
Deferred tax liabilities: |  |
Deferred policy acquisition costs | (45,178) | (41,612)
Tax liability on net unrealized gain on securities carried at fair value | 0 | (27,574)
Tax depreciation in excess of book depreciation | (4,594) | (5,686)
Undistributed earnings of insurance subsidiaries | (3,017) | (3,907)
Tax amortization in excess of book amortization | (2,729) | (2,280)
Other deferred tax liabilities | (4,719) | (5,417)
Total gross deferred tax liabilities | (60,237) | (86,476)
Net deferred tax assets | $ 13,339 |
Net deferred tax liabilities |  | $ (22,932)

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