Investments (Components Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Dividends on equity securities	$ 40,195	$ 32,693
Total investment income	242,987	223,431
Investment expenses	(5,892)	(5,162)
Net investment income	237,095	218,269
Fixed Maturity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	143,345	119,476
Short-term investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	19,673	32,184
Cash and Cash Equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	$ 39,774	$ 39,078

Amount of dividend 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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