Investments (Components Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Dividends on equity securities	$ 26,352	$ 23,590	$ 53,834	$ 48,327
Total investment income	173,974	100,887	337,804	197,544
Investment expenses	(4,281)	(4,092)	(8,776)	(8,445)
Net investment income	169,693	96,795	329,028	189,099
Fixed Maturities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	88,419	71,920	170,547	143,064
Short-term investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	23,712	3,354	50,331	4,328
Cash and Cash Equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	$ 35,491	$ 2,023	$ 63,092	$ 1,825

Amount of dividend income on nonoperating securities.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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