Available-for-Sale and Held-to-Maturity Securities (Schedule of Gross Unrealized Losses and Estimated Fair Value by Length of Time) (Details) $ in Thousands	Dec. 31, 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	$ (1,866)
Available-for-sale Securities, Estimated fair value, Less than 12 months	198,982
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(168,781)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,258,245
Available-for-sale Securities, Gross unrealized losses, Total	(170,647)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,457,227
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	(1)
Available-for-sale Securities, Estimated fair value, Less than 12 months	453
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(140)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,813
Available-for-sale Securities, Gross unrealized losses, Total	(141)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	2,266
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	(1)
Available-for-sale Securities, Estimated fair value, Less than 12 months	2,349
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	(1)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	2,349
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	(43,832)
Available-for-sale Securities, Estimated fair value, 12 months or more	463,992
Available-for-sale Securities, Gross unrealized losses, Total	(43,832)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	463,992
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	(1,852)
Available-for-sale Securities, Estimated fair value, Less than 12 months	189,220
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(122,263)
Available-for-sale Securities, Estimated fair value, 12 months or more	637,174
Available-for-sale Securities, Gross unrealized losses, Total	(124,115)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	826,394
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	(1,474)
Available-for-sale Securities, Estimated fair value, 12 months or more	67,956
Available-for-sale Securities, Gross unrealized losses, Total	(1,474)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	67,956
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	(7)
Available-for-sale Securities, Estimated fair value, 12 months or more	199
Available-for-sale Securities, Gross unrealized losses, Total	(7)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	199
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	(12)
Available-for-sale Securities, Estimated fair value, Less than 12 months	6,960
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(1,065)
Available-for-sale Securities, Estimated fair value, 12 months or more	87,111
Available-for-sale Securities, Gross unrealized losses, Total	(1,077)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 94,071

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