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	Mar. 31, 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	$ (8,123)
Available-for-sale Securities, Estimated fair value, Less than 12 months	238,363
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(188,738)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,342,346
Available-for-sale Securities, Gross unrealized losses, Total	(196,861)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,580,709
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	(175)
Available-for-sale Securities, Estimated fair value, Less than 12 months	1,752
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	(175)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,752
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	(2,614)
Available-for-sale Securities, Estimated fair value, Less than 12 months	58,582
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(69,768)
Available-for-sale Securities, Estimated fair value, 12 months or more	489,235
Available-for-sale Securities, Gross unrealized losses, Total	(72,382)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	547,817
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	(3,990)
Available-for-sale Securities, Estimated fair value, Less than 12 months	104,347
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(111,940)
Available-for-sale Securities, Estimated fair value, 12 months or more	685,830
Available-for-sale Securities, Gross unrealized losses, Total	(115,930)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	790,177
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	(4,476)
Available-for-sale Securities, Estimated fair value, 12 months or more	66,691
Available-for-sale Securities, Gross unrealized losses, Total	(4,476)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	66,691
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	(30)
Available-for-sale Securities, Estimated fair value, Less than 12 months	392
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	(30)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	392
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	(1,314)
Available-for-sale Securities, Estimated fair value, Less than 12 months	73,290
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(2,554)
Available-for-sale Securities, Estimated fair value, 12 months or more	100,590
Available-for-sale Securities, Gross unrealized losses, Total	(3,868)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 173,880

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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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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