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Income Taxes (Components Of Domestic And Foreign Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Income Tax Disclosure [Abstract] |  |
Unpaid losses and loss adjustment expenses | $ 233,583 | $ 216,863
Lease liabilities | 172,131 | 161,350
Unearned premiums | 164,485 | 168,172
Accrued incentive compensation | 51,943 | 52,853
Tax credit carryforwards | 45,481 | 25,396
Net operating loss carryforwards | 37,168 | 43,439
Life and annuity benefits | 29,143 | 39,729
Other differences between financial reporting and tax bases | 106,667 | 93,693
Total gross deferred tax assets | 840,601 | 801,495
Less valuation allowance | (33,292) | (13,916)
Total gross deferred tax assets, net of allowance | 807,309 | 787,579
Investments | 1,566,540 | 1,196,717
Deferred policy acquisition costs | 173,742 | 176,382
Goodwill and other intangible assets | 170,941 | 175,767
Right-of-use lease assets | 162,628 | 152,939
Property, plant and equipment | 160,615 | 152,149
Other differences between financial reporting and tax bases | 113,873 | 104,024
Total gross deferred tax liabilities | 2,348,339 | 1,957,978
Deferred tax liability, net | $ 1,541,030 | $ 1,170,399

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