Investments In Securities and Fair Value (Schedule Of Gross Realized and Unrealized Gains And Losses On Securities) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Marketable Security, Gain (Loss) [Abstract]
Corporate debt securities, realized gains	$ 1	$ 2	$ 35	$ 5
Equity securities, realized gains	2,031	1,599	2,220	4,156
Debit and equity securities, realized gains	2,032	1,601	2,255	4,161
Corporate debt securities, realized losses	(6)	0	(6)	0
Equity securities, realized losses	(166)	(326)	(272)	(613)
Debt and equity securities, realized loss	(172)	(326)	(278)	(613)
Debt and equity securities, net realized gain (loss)	1,860	1,275	1,977	3,548
Gross gains on other investments	0	0	0	1
Write-down of other assets	(362)	(144)	(362)	(419)
Net gains (losses) on other investments	(362)	(144)	(362)	(418)
Net realized investment gains (losses)	1,498	1,131	1,615	3,130
Changes in the estimated fair value of equity investments	3,297	973	3,704	(2,205)
Net investment gains (losses)	$ 4,795	$ 2,104	$ 5,319	$ 925

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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Gains 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 gain on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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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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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 realized and unrealized gain (loss) on investment.

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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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Amount of realized gain (loss) on investment.

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