Investments (Summary Of Gross Gains (Losses) From Sales Of Fixed Maturity And Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities				$ 2,054
Proceeds from equity securities sold - at fair value			450,319	328,519
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities	$ 151,932	$ 84,822	394,004	422,545
Gross gains from sales	8,868	4,977	24,067	15,578
Gross losses from sales	(6,143)	(6,976)	(13,287)	(36,551)
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from equity securities sold - at fair value	104,231	115,516	450,319	328,519
Gross gains from sales	2,769	9,503	17,706	30,256
Gross losses from sales	$ (3,257)	$ (9,784)	$ (11,371)	$ (41,865)

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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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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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