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	$ 81,975	$ 281,313
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of fixed maturity securities	266,665	76,628
Gross gains from dispositions	3,155	6,349
Gross losses from dispositions	(8,244)	(2,422)
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of equity securities	81,975	281,313
Gross gains from dispositions	3,508	12,304
Gross losses from dispositions	$ (11,776)	$ (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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