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	Sep. 30, 2024 USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (298)
Available-for-sale Securities, Estimated fair value, Less than 12 months	20,638
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(135,104)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,332,535
Available-for-sale Securities, Gross unrealized losses, Total	(135,402)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,353,173
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	(111)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,839
Available-for-sale Securities, Gross unrealized losses, Total	(111)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,839
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	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(39,486)
Available-for-sale Securities, Estimated fair value, 12 months or more	486,817
Available-for-sale Securities, Gross unrealized losses, Total	(39,486)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	486,817
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	(281)
Available-for-sale Securities, Estimated fair value, Less than 12 months	12,388
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(92,894)
Available-for-sale Securities, Estimated fair value, 12 months or more	682,765
Available-for-sale Securities, Gross unrealized losses, Total	(93,175)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	695,153
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	(1,761)
Available-for-sale Securities, Estimated fair value, 12 months or more	67,898
Available-for-sale Securities, Gross unrealized losses, Total	(1,761)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	67,898
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	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(9)
Available-for-sale Securities, Estimated fair value, 12 months or more	215
Available-for-sale Securities, Gross unrealized losses, Total	(9)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	215
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	(17)
Available-for-sale Securities, Estimated fair value, Less than 12 months	8,250
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(843)
Available-for-sale Securities, Estimated fair value, 12 months or more	93,001
Available-for-sale Securities, Gross unrealized losses, Total	(860)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 101,251

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