Investments (Components Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Dividends on equity securities	$ 34,812	$ 31,831	$ 75,007	$ 64,524
Total investment income	235,944	227,216	478,931	450,647
Investment expenses	(5,935)	(4,155)	(11,827)	(9,317)
Net investment income	230,009	223,061	467,104	441,330
Fixed Maturity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	145,829	121,189	289,174	240,665
Short-term investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	19,580	31,654	39,253	63,838
Cash and Cash Equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	$ 35,723	$ 42,542	$ 75,497	$ 81,620

Amount of dividend income on nonoperating securities.

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Amount of expenses related to the generation of investment income.

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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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