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Income Taxes - Deferred Tax Assets And Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Deferred tax assets: |  |
20% of net unearned premiums | $ 75,394 | $ 67,285
Discounting of loss reserves and salvage and subrogation recoverable for tax purposes | 25,340 | 21,606
Expense accruals | 11,262 | 11,578
Tax asset on net unrealized loss on securities carried at fair value | 166 | 22,802
Other deferred tax assets | 8,743 | 6,511
Total gross deferred tax assets | 120,905 | 129,782
Deferred tax liabilities: |  |
Deferred policy acquisition costs | (61,707) | (55,960)
Tax depreciation in excess of book depreciation | (6,801) | (11,029)
Undistributed earnings of insurance subsidiaries | (1,511) | (1,898)
Tax amortization in excess of book amortization | (8,904) | (7,466)
Other deferred tax liabilities | (8,969) | (10,526)
Total gross deferred tax liabilities | (87,892) | (86,879)
Net deferred tax assets | $ 33,013 | $ 42,903

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