Investments (Summary Of Gross Gains (Losses) From Sales Of Fixed Maturity And Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities	$ 173,479	$ 403,419	$ 337,723	$ 2,007,308
Gross gains from sales	8,755	3,133	10,601	11,237
Gross losses from sales	(6,792)	(5,090)	(29,575)	(9,768)
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities	8,842	79,735	213,003	148,973
Gross gains from sales	18,172	2,577	20,753	8,248
Gross losses from sales	$ (1,898)	$ (3,891)	$ (32,081)	$ (4,518)

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

No definition available.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26853-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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