Investments (Summary Of Gross Gains (Losses) From Sales Of Fixed Maturity And Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of equity securities	$ 90,101	$ 281,313
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities	418,988	228,278
Gross gains from sales	20,122	14,864
Gross losses from sales	(17,324)	(5,690)
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of equity securities	90,101	281,313
Gross gains from sales	3,508	12,304
Gross losses from sales	$ (15,294)	$ (6,066)

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
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