Available-For-Sale And Held-To-Maturity Securities (Schedule Of Gross Unrealized Losses And The Estimated Fair Value By Length Of Time In A Loss Position) (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (13,547)
Available-for-sale Securities, Estimated fair value, Less than 12 months	922,044
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(3,479)
Available-for-sale Securities, Estimated fair value, 12 months or more	139,835
Available-for-sale Securities, Gross unrealized losses, Total	(17,026)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,061,879
Asset-Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(1,933)
Available-for-sale Securities, Estimated fair value, Less than 12 months	117,388
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(296)
Available-for-sale Securities, Estimated fair value, 12 months or more	35,800
Available-for-sale Securities, Gross unrealized losses, Total	(2,229)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	153,188
Agency Mortgage-Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(5,833)
Available-for-sale Securities, Estimated fair value, Less than 12 months	499,332
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(3,183)
Available-for-sale Securities, Estimated fair value, 12 months or more	104,035
Available-for-sale Securities, Gross unrealized losses, Total	(9,016)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	603,367
Corporate Fixed Income Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(5,781)
Available-for-sale Securities, Estimated fair value, Less than 12 months	305,324
Available-for-sale Securities, Gross unrealized losses, 12 months or more
Available-for-sale Securities, Estimated fair value, 12 months or more
Available-for-sale Securities, Gross unrealized losses, Total	(5,781)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 305,324

Schedule of available for sale and held to maturity securities.

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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