Available-for-Sale and Held-to-Maturity Securities (Schedule of Gross Unrealized Losses and Estimated Fair Value by Length of Time in a Loss Position) (Details) - USD ($) $ in Thousands	Mar. 31, 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	$ (5,108)	$ (1,379)
Available-for-sale Securities, Estimated fair value, Less than 12 months	361,670	155,531
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(111,827)	(108,681)
Available-for-sale Securities, Estimated fair value, 12 months or more	947,676	999,481
Available-for-sale Securities, Gross unrealized losses, Total	(116,935)	(110,060)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,309,346	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	(65)	(65)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,909	1,905
Available-for-sale Securities, Gross unrealized losses, Total	(65)	(65)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,909	1,905
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	(1,306)	(1,201)
Available-for-sale Securities, Estimated fair value, Less than 12 months	13,108	23,252
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(25,286)	(23,196)
Available-for-sale Securities, Estimated fair value, 12 months or more	316,538	333,905
Available-for-sale Securities, Gross unrealized losses, Total	(26,592)	(24,397)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	329,646	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	(3,793)	(178)
Available-for-sale Securities, Estimated fair value, Less than 12 months	326,871	132,279
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(86,175)	(84,950)
Available-for-sale Securities, Estimated fair value, 12 months or more	576,777	599,689
Available-for-sale Securities, Gross unrealized losses, Total	(89,968)	(85,128)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	903,648	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	(24)	(23)
Available-for-sale Securities, Estimated fair value, 12 months or more	1,318	2,113
Available-for-sale Securities, Gross unrealized losses, Total	(24)	(23)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,318	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	(4)	(4)
Available-for-sale Securities, Estimated fair value, 12 months or more	138	152
Available-for-sale Securities, Gross unrealized losses, Total	(4)	(4)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	138	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	(9)	0
Available-for-sale Securities, Estimated fair value, Less than 12 months	21,691	0
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(273)	(443)
Available-for-sale Securities, Estimated fair value, 12 months or more	50,996	61,717
Available-for-sale Securities, Gross unrealized losses, Total	(282)	(443)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 72,687	$ 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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