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	Jun. 30, 2023 USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (8,396)
Available-for-sale Securities, Estimated fair value, Less than 12 months	181,735
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(206,680)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,389,257
Available-for-sale Securities, Gross unrealized losses, Total	(215,076)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,570,992
U.S. Government Agency 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	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(199)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,730
Available-for-sale Securities, Gross unrealized losses, Total	(199)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,730
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	(3,991)
Available-for-sale Securities, Estimated fair value, Less than 12 months	46,252
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(72,184)
Available-for-sale Securities, Estimated fair value, 12 months or more	497,209
Available-for-sale Securities, Gross unrealized losses, Total	(76,175)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	543,461
Mortgage-Backed Securities [Member] \| Agency 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	(3,621)
Available-for-sale Securities, Estimated fair value, Less than 12 months	66,805
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(125,752)
Available-for-sale Securities, Estimated fair value, 12 months or more	701,743
Available-for-sale Securities, Gross unrealized losses, Total	(129,373)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	768,548
Mortgage-Backed Securities [Member] \| Commercial [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(5,308)
Available-for-sale Securities, Estimated fair value, 12 months or more	65,578
Available-for-sale Securities, Gross unrealized losses, Total	(5,308)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	65,578
Mortgage-Backed Securities [Member] \| Non 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	(25)
Available-for-sale Securities, Estimated fair value, Less than 12 months	343
Available-for-sale Securities, Gross unrealized losses, 12 months or more	0
Available-for-sale Securities, Estimated fair value, 12 months or more	0
Available-for-sale Securities, Gross unrealized losses, Total	(25)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	343
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	(759)
Available-for-sale Securities, Estimated fair value, Less than 12 months	68,335
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(3,237)
Available-for-sale Securities, Estimated fair value, 12 months or more	122,997
Available-for-sale Securities, Gross unrealized losses, Total	(3,996)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 191,332

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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.

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