Investments In Securities and Fair Value (Schedule Of Unrealized Losses On Investments) (Details) $ in Thousands	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	13	9
Special revenue issuer obligations of U.S. states, territories and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Total temporarily impaired securities, Less than 12 Months, Fair Value	$ 2,383	$ 0
Total temporarily impaired securities, Less than 12 Months, Unrealized Losses	(53)	0
Total temporarily impaired securities, 12 Months or Longer, Fair Value	1,101	1,102
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(3)	(2)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	3,484	1,102
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(56)	(2)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Total temporarily impaired securities, Less than 12 Months, Fair Value	2,633	8,493
Total temporarily impaired securities, Less than 12 Months, Unrealized Losses	(69)	(13)
Total temporarily impaired securities, 12 Months or Longer, Fair Value	6,111	6,203
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(96)	(35)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	8,744	14,696
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(165)	(48)
Total temporarily impaired securities
Debt Securities, Available-for-sale [Line Items]
Total temporarily impaired securities, Less than 12 Months, Fair Value	5,016	8,493
Total temporarily impaired securities, Less than 12 Months, Unrealized Losses	(122)	(13)
Total temporarily impaired securities, 12 Months or Longer, Fair Value	7,212	7,305
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(99)	(37)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	12,228	15,798
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (221)	$ (50)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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