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) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (37,519)	$ (1,379)
Available-for-sale Securities, Estimated fair value, Less than 12 months	709,161	155,531
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(140,714)	(108,681)
Available-for-sale Securities, Estimated fair value, 12 months or more	765,925	999,481
Available-for-sale Securities, Gross unrealized losses, Total	(178,233)	(110,060)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,475,086	1,155,012
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	(2)	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	480	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(61)	(65)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,922	1,905
Available-for-sale Securities, Gross unrealized losses, Total	(63)	(65)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	2,402	1,905
State and Municipal 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	(34)
Available-for-sale Securities, Estimated fair value, Less than 12 months	2,291
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	(34)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	2,291
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	(1,615)	(1,201)
Available-for-sale Securities, Estimated fair value, Less than 12 months	17,719	23,252
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(29,361)	(23,196)
Available-for-sale Securities, Estimated fair value, 12 months or more	226,282	333,905
Available-for-sale Securities, Gross unrealized losses, Total	(30,976)	(24,397)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	244,001	357,157
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	(35,868)	(178)
Available-for-sale Securities, Estimated fair value, Less than 12 months	688,671	132,279
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(111,119)	(84,950)
Available-for-sale Securities, Estimated fair value, 12 months or more	510,687	599,689
Available-for-sale Securities, Gross unrealized losses, Total	(146,987)	(85,128)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,199,358	731,968
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	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	0	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(26)	(23)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,243	2,113
Available-for-sale Securities, Gross unrealized losses, Total	(26)	(23)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,243	2,113
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	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	0	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(2)	(4)
Available-for-sale Securities, Estimated fair value, 12 months or more	124	152
Available-for-sale Securities, Gross unrealized losses, Total	(2)	(4)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	124	152
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		0
Available-for-sale Securities, Estimated fair value, Less than 12 months		0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(145)	(443)
Available-for-sale Securities, Estimated fair value, 12 months or more	25,667	61,717
Available-for-sale Securities, Gross unrealized losses, Total	(145)	(443)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 25,667	$ 61,717

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