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	Jun. 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	$ (6,127)	$ (1,379)
Available-for-sale Securities, Estimated fair value, Less than 12 months	363,325	155,531
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(111,898)	(108,681)
Available-for-sale Securities, Estimated fair value, 12 months or more	914,244	999,481
Available-for-sale Securities, Gross unrealized losses, Total	(118,025)	(110,060)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,277,569	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	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	(63)	(65)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,916	1,905
Available-for-sale Securities, Gross unrealized losses, Total	(63)	(65)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,916	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	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(5)
Available-for-sale Securities, Estimated fair value, 12 months or more	2,320
Available-for-sale Securities, Gross unrealized losses, Total	(5)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	2,320
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	(1,275)	(1,201)
Available-for-sale Securities, Estimated fair value, Less than 12 months	13,098	23,252
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(23,347)	(23,196)
Available-for-sale Securities, Estimated fair value, 12 months or more	318,246	333,905
Available-for-sale Securities, Gross unrealized losses, Total	(24,622)	(24,397)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	331,344	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	(4,826)	(178)
Available-for-sale Securities, Estimated fair value, Less than 12 months	326,441	132,279
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(88,119)	(84,950)
Available-for-sale Securities, Estimated fair value, 12 months or more	552,962	599,689
Available-for-sale Securities, Gross unrealized losses, Total	(92,945)	(85,128)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	879,403	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	(33)	(23)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,269	2,113
Available-for-sale Securities, Gross unrealized losses, Total	(33)	(23)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,269	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	(1)	(4)
Available-for-sale Securities, Estimated fair value, 12 months or more	133	152
Available-for-sale Securities, Gross unrealized losses, Total	(1)	(4)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	133	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	(26)	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	23,786	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(330)	(443)
Available-for-sale Securities, Estimated fair value, 12 months or more	37,398	61,717
Available-for-sale Securities, Gross unrealized losses, Total	(356)	(443)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 61,184	$ 61,717

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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.

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