Investments In Securities and Fair Value (Schedule Of Gross Realized Gains And Losses On Securities) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Equity securities, realized gains	$ 1,747	$ 940
Debit and equity securities, realized gains	1,747	940
Debt Securities, Available-for-sale, Realized Loss	0	(23)
Equity securities, realized losses	0	(596)
Other-than-temporary impairment, gross realized losses	0
Debt and Equity Securities, Realized Loss	0	(619)
Debt and equity securities, net realized gain (loss)	1,747	321
Gross gains on sales of other investments	0	0
Gross losses on sales of other investments	0	0
Net gains (losses) on sales of other investments	0	0
Net realized investment gains (losses)	$ 1,747	$ 321

Amount of realized gain on investments in debt and equity securities

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Amount of realized loss on investments in debt and equity securities

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Amount of gain included in earnings for investments classified as other.

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Losses on Other Assets and Investments

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Amount of realized gain (loss) on investment in debt and equity securities.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
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Amount of realized loss 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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Amount of gain (loss) included in earnings for investments classified as other.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings.

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Amount of realized gain (loss) on investment.

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-SubTopic 220
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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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