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Income Taxes (Components Of Domestic And Foreign Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Income Tax Disclosure [Abstract] |  |
Unpaid losses and loss adjustment expenses | $ 216,863 | $ 170,518
Unearned premiums | 168,172 | 161,243
Lease liabilities | 161,350 | 132,735
Life and annuity benefits | 39,729 | 32,149
Accrued incentive compensation | 52,853 | 39,469
Net operating loss carryforwards | 43,439 | 25,305
Tax credit carryforwards | 25,396 | 18,264
Other differences between financial reporting and tax bases | 93,693 | 65,250
Total gross deferred tax assets | 801,495 | 644,933
Less valuation allowance | (13,916) | (16,943)
Total gross deferred tax assets, net of allowance | 787,579 | 627,990
Investments | 1,196,717 | 761,421
Goodwill and other intangible assets | 175,767 | 180,186
Deferred policy acquisition costs | 176,382 | 161,220
Property, plant and equipment | 152,149 | 144,259
Right-of-use lease assets | 152,939 | 127,398
Other differences between financial reporting and tax bases | 104,024 | 113,065
Total gross deferred tax liabilities | 1,957,978 | 1,487,549
Deferred tax liability, net | $ 1,170,399 | $ 859,559

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