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Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Deferred tax asset: |  |
Loss reserve discounting | $ 230,956 | $ 192,181
Unearned premiums | 200,938 | 180,326
Unrealized investment losses | 126,693 | 228,456
Net operating losses & foreign tax credits | 59,154 | 58,182
Other-than-temporary impairments | 12,691 | 5,935
Employee compensation plans | 68,062 | 63,313
Other | 78,025 | 72,536
Gross deferred tax asset | 776,519 | 800,929
Less valuation allowance | (36,283) | (47,166)
Deferred tax asset | 740,236 | 753,763
Deferred tax liability: |  |
Amortization of intangibles | 15,205 | 13,973
Loss reserve discounting - transition rule | 9,894 | 14,843
Deferred policy acquisition costs | 176,281 | 157,055
Property, furniture and equipment | 43,501 | 45,887
Investment funds | 161,867 | 125,525
Other | 66,525 | 67,479
Deferred tax liability | 473,273 | 424,762
Net deferred tax asset | 266,963 | 329,001
Operating Loss Carryforwards [Line Items] |  |
Income taxes receivable |  | 5,000
Current federal income taxes | 46,000 |
Valuation allowance | 36,000 | $ 47,000
Foreign Tax Authority |  |
Operating Loss Carryforwards [Line Items] |  |
Operating loss carryforwards, subject to expire | $ 220,000 |

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