Investments (Components Of Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Dividends on equity securities	$ 38,182	$ 35,762	$ 131,345	$ 110,769
Total investment income	261,258	248,296	781,997	727,227
Investment expenses	(3,143)	(2,621)	(11,869)	(14,448)
Net investment income	258,115	245,675	770,128	712,779
Fixed Maturity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	171,041	155,645	504,561	444,819
Short-term investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	21,981	19,406	56,784	58,659
Cash and Cash Equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Interest income	$ 30,054	$ 37,483	$ 89,307	$ 112,980

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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