Investments (Components Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Dividends on equity securities	$ 32,693	$ 27,482
Total investment income	223,431	163,830
Investment expenses	(5,162)	(4,495)
Net investment income	218,269	159,335
Fixed Maturities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	119,476	82,128
Short-term investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	32,184	26,619
Cash and Cash Equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	$ 39,078	$ 27,601

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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