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Investment Securities (Investments Gross Unrealized Losses and Fair Value) (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
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Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 14 | $ 193,800
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 17,922
Securities available for sale, 12 months or longer, Fair Value | 853,876 | 760,210
Securities available for sale, 12 months or longer, Unrealized Losses | 207,291 | 155,102
Securities available for sale, Fair Value, Total | 853,890 | 954,010
Securities available for sale, Unrealized Losses, Total | 207,291 | 173,024
Total AFS debt securities with unrealized losses, Less than 12 months, Fair Value | 14 | 193,800
Total AFS debt securities with unrealized losses, Less than 12 months, Unrealized Losses | 0 | 17,922
Total AFS debt securities with unrealized losses, 12 months or longer, Fair Value | 853,876 | 760,210
Total AFS debt securities with unrealized losses, 12 months or longer, Unrealized Losses | 207,291 | 155,102
Total AFS debt securities with unrealized losses, Fair Value | 853,890 | 954,010
Total AFS debt securities with unrealized losses, Unrealized Losses | 207,291 | 173,024
U.S. Government Agency And Government Sponsored Enterprises [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 0 | 0
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 0
Securities available for sale, 12 months or longer, Fair Value | 20,909 | 21,115
Securities available for sale, 12 months or longer, Unrealized Losses | 3,626 | 3,420
Securities available for sale, Fair Value, Total | 20,909 | 21,115
Securities available for sale, Unrealized Losses, Total | 3,626 | 3,420
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 0 | 1,000
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 94
Securities available for sale, 12 months or longer, Fair Value | 8,446 | 8,572
Securities available for sale, 12 months or longer, Unrealized Losses | 2,773 | 2,509
Securities available for sale, Fair Value, Total | 8,446 | 9,572
Securities available for sale, Unrealized Losses, Total | 2,773 | 2,603
Collateralized Mortgage Obligations [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 0 | 0
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 0
Securities available for sale, 12 months or longer, Fair Value | 15,078 | 17,356
Securities available for sale, 12 months or longer, Unrealized Losses | 5,121 | 4,163
Securities available for sale, Fair Value, Total | 15,078 | 17,356
Securities available for sale, Unrealized Losses, Total | 5,121 | 4,163
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 14 | 193,800
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 17,922
Securities available for sale, 12 months or longer, Fair Value | 832,967 | 739,095
Securities available for sale, 12 months or longer, Unrealized Losses | 203,665 | 151,682
Securities available for sale, Fair Value, Total | 832,981 | 932,895
Securities available for sale, Unrealized Losses, Total | 203,665 | 169,604
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 14 | 154,006
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 14,708
Securities available for sale, 12 months or longer, Fair Value | 425,724 | 315,598
Securities available for sale, 12 months or longer, Unrealized Losses | 88,324 | 61,485
Securities available for sale, Fair Value, Total | 425,738 | 469,604
Securities available for sale, Unrealized Losses, Total | 88,324 | 76,193
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 0 | 28,493
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 2,199
Securities available for sale, 12 months or longer, Fair Value | 300,727 | 313,728
Securities available for sale, 12 months or longer, Unrealized Losses | 81,037 | 66,409
Securities available for sale, Fair Value, Total | 300,727 | 342,221
Securities available for sale, Unrealized Losses, Total | 81,037 | 68,608
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 0 | 10,301
Securities available for sale, Less than 12 months, Unrealized Losses | 0 | 921
Securities available for sale, 12 months or longer, Fair Value | 82,992 | 83,841
Securities available for sale, 12 months or longer, Unrealized Losses | 26,410 | 17,116
Securities available for sale, Fair Value, Total | 82,992 | 94,142
Securities available for sale, Unrealized Losses, Total | $ 26,410 | $ 18,037

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