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Income Taxes (Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Deferred tax assets: |  |
20% of net unearned premiums | $ 58,448 | $ 52,644
Discounting of loss reserves and salvage and subrogation recoverable for tax purposes | 12,769 | 9,245
Write-down of impaired investments | 314 | 356
Expense accruals | 8,099 | 7,019
Tax asset on net unrealized loss on securities carried at fair value | 0 | 1,055
Other deferred tax assets | 3,348 | 3,257
Total gross deferred tax assets | 82,978 | 73,576
Deferred tax liabilities: |  |
Deferred policy acquisition costs | (48,964) | (45,178)
Tax liability on net unrealized gain on securities carried at fair value | (41,273) | 0
Tax depreciation in excess of book depreciation | (8,105) | (4,594)
Undistributed earnings of insurance subsidiaries | (2,855) | (3,017)
Tax amortization in excess of book amortization | (3,264) | (2,729)
Other deferred tax liabilities | (6,481) | (4,719)
Total gross deferred tax liabilities | (110,942) | (60,237)
Net deferred tax (liabilities) assets | $ (27,964) |
Net deferred tax (liabilities) assets |  | $ 13,339

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