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, 2025 USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (1,103)
Available-for-sale Securities, Estimated fair value, Less than 12 months	253,688
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(116,086)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,086,210
Available-for-sale Securities, Gross unrealized losses, Total	(117,189)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,339,898
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	(77)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,889
Available-for-sale Securities, Gross unrealized losses, Total	(77)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,889
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	(64)
Available-for-sale Securities, Estimated fair value, Less than 12 months	9,935
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(25,782)
Available-for-sale Securities, Estimated fair value, 12 months or more	382,382
Available-for-sale Securities, Gross unrealized losses, Total	(25,846)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	392,317
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	(1,014)
Available-for-sale Securities, Estimated fair value, Less than 12 months	232,197
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(89,336)
Available-for-sale Securities, Estimated fair value, 12 months or more	621,946
Available-for-sale Securities, Gross unrealized losses, Total	(90,350)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	854,143
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	(121)
Available-for-sale Securities, Estimated fair value, 12 months or more	10,976
Available-for-sale Securities, Gross unrealized losses, Total	(121)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	10,976
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	(6)
Available-for-sale Securities, Estimated fair value, 12 months or more	158
Available-for-sale Securities, Gross unrealized losses, Total	(6)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	158
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	(25)
Available-for-sale Securities, Estimated fair value, Less than 12 months	11,556
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(764)
Available-for-sale Securities, Estimated fair value, 12 months or more	68,859
Available-for-sale Securities, Gross unrealized losses, Total	(789)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 80,415

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