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Income Taxes (Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Deferred tax assets: |  |
20% of net unearned premiums | $ 61,067 | $ 58,448
Discounting of loss reserves and salvage and subrogation recoverable for tax purposes | 15,090 | 12,769
Write-down of impaired investments | 293 | 314
Expense accruals | 14,432 | 8,099
Other deferred tax assets | 6,401 | 3,348
Total gross deferred tax assets | 97,283 | 82,978
Deferred tax liabilities: |  |
Deferred policy acquisition costs | (51,869) | (48,964)
Tax liability on net unrealized gain on securities carried at fair value | (56,531) | (41,273)
Tax depreciation in excess of book depreciation | (12,632) | (8,105)
Undistributed earnings of insurance subsidiaries | (3,382) | (2,855)
Tax amortization in excess of book amortization | (4,666) | (3,264)
Other deferred tax liabilities | (9,335) | (6,481)
Total gross deferred tax liabilities | (138,415) | (110,942)
Net deferred tax liabilities | $ (41,132) | $ (27,964)

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