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Available-for-Sale and Held-to-Maturity Securities (Schedule of Gross Unrealized Losses and Estimated Fair Value by Length of Time) (Details) $ in Thousands | Sep. 30, 2023 USD ($)
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Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |
Available-for-sale Securities, Gross unrealized losses, Less than 12 months | $ (3,176)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 97,267
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (247,335)
Available-for-sale Securities, Estimated fair value, 12 months or more | 1,412,468
Available-for-sale Securities, Gross unrealized losses, Total | (250,511)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 1,509,735
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 | (8)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 427
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (225)
Available-for-sale Securities, Estimated fair value, 12 months or more | 1,708
Available-for-sale Securities, Gross unrealized losses, Total | (233)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 2,135
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 | (56)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 2,294
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 | (56)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 2,294
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 | (235)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 6,438
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (80,084)
Available-for-sale Securities, Estimated fair value, 12 months or more | 528,914
Available-for-sale Securities, Gross unrealized losses, Total | (80,319)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 535,352
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 | (1,228)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 24,100
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (159,529)
Available-for-sale Securities, Estimated fair value, 12 months or more | 691,150
Available-for-sale Securities, Gross unrealized losses, Total | (160,757)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 715,250
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 | (4,868)
Available-for-sale Securities, Estimated fair value, 12 months or more | 65,695
Available-for-sale Securities, Gross unrealized losses, Total | (4,868)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 65,695
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 | (19)
Available-for-sale Securities, Estimated fair value, 12 months or more | 332
Available-for-sale Securities, Gross unrealized losses, Total | (19)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 332
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 | (1,649)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 64,008
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (2,610)
Available-for-sale Securities, Estimated fair value, 12 months or more | 124,669
Available-for-sale Securities, Gross unrealized losses, Total | (4,259)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | $ 188,677

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