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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 | Mar. 31, 2025 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 | $ (761)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 92,182
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (143,110)
Available-for-sale Securities, Estimated fair value, 12 months or more | 1,185,928
Available-for-sale Securities, Gross unrealized losses, Total | (143,871)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 1,278,110
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
Available-for-sale Securities, Estimated fair value, Less than 12 months | 0
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (109)
Available-for-sale Securities, Estimated fair value, 12 months or more | 1,849
Available-for-sale Securities, Gross unrealized losses, Total | (109)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 1,849
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 | (36,158)
Available-for-sale Securities, Estimated fair value, 12 months or more | 428,765
Available-for-sale Securities, Gross unrealized losses, Total | (36,158)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 428,765
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 | (581)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 59,153
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (105,138)
Available-for-sale Securities, Estimated fair value, 12 months or more | 632,161
Available-for-sale Securities, Gross unrealized losses, Total | (105,719)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 691,314
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 | (938)
Available-for-sale Securities, Estimated fair value, 12 months or more | 66,417
Available-for-sale Securities, Gross unrealized losses, Total | (938)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 66,417
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 | (6)
Available-for-sale Securities, Estimated fair value, 12 months or more | 177
Available-for-sale Securities, Gross unrealized losses, Total | (6)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | 177
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 | (180)
Available-for-sale Securities, Estimated fair value, Less than 12 months | 33,029
Available-for-sale Securities, Gross unrealized losses, 12 months or more | (761)
Available-for-sale Securities, Estimated fair value, 12 months or more | 56,559
Available-for-sale Securities, Gross unrealized losses, Total | (941)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total | $ 89,588

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