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Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | $ 1,061,181 | $ 1,127,057
Securities available for sale, Unrealized Gains | 325 | 338
Securities available for sale, Unrealized Losses | 207,291 | 173,024
Securities available for sale | 854,215 | 954,371
Securities held to maturity, Amortized Cost | 154,208 | 188,980
Securities held to maturity, Unrealized Gains | 20 | 24
Securities held to maturity, Unrealized Losses | 17,688 | 14,816
Securities held to maturity, fair value | 136,540 | 174,188
Allowance for credit losses, Amortized Cost | (4) | (5)
Held-to-maturity securities, net , Amortized Cost | 154,204 | 188,975
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, Amortized Cost | 24,535 | 24,535
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 3,626 | 3,420
Securities available for sale | 20,909 | 21,115
Securities held to maturity, Amortized Cost | 16,476 | 16,363
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 1,095 | 848
Securities held to maturity, fair value | 15,381 | 15,515
State And Political Subdivisions [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities held to maturity, Amortized Cost | 72,666 | 97,583
Securities held to maturity, Unrealized Gains | 20 | 24
Securities held to maturity, Unrealized Losses | 8,374 | 7,172
Securities held to maturity, fair value | 64,312 | 90,435
Collateralized Mortgage Obligations Government National Mortgage Association Certificates And Obligations Gnma [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities held to maturity, Amortized Cost | 3,714 | 4,222
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 368 | 330
Securities held to maturity, fair value | 3,346 | 3,892
Collateralized Mortgage Obligations Federal National Mortgage Association Certificates and Obligations (FNMA) [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 11,219 | 12,175
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 2,773 | 2,603
Securities available for sale | 8,446 | 9,572
Securities held to maturity, Amortized Cost | 12,088 | 14,268
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 1,165 | 1,119
Securities held to maturity, fair value | 10,923 | 13,149
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 1,036,646 | 1,102,522
Securities available for sale, Unrealized Gains | 325 | 338
Securities available for sale, Unrealized Losses | 203,665 | 169,604
Securities available for sale | 833,306 | 933,256
Securities held to maturity, Amortized Cost | 65,066 | 75,034
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 8,219 | 6,796
Securities held to maturity, fair value | 56,847 | 68,238
Collateralized Mortgage-Backed Securities Government National Mortgage Association Certificates and Obligations (GNMA) [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 109,402 | 112,202
Securities available for sale, Unrealized Gains | 0 | 1
Securities available for sale, Unrealized Losses | 26,410 | 18,037
Securities available for sale | 82,992 | 94,166
Securities held to maturity, Amortized Cost | 20,655 | 22,541
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 2,806 | 2,116
Securities held to maturity, fair value | 17,849 | 20,425
Collateralized Mortgage-Backed Securities Federal National Mortgage Association Certificates and Obligations (FNMA) [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 514,062 | 545,797
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 88,324 | 76,193
Securities available for sale | 425,738 | 469,604
Securities held to maturity, Amortized Cost | 5,942 | 8,332
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 809 | 582
Securities held to maturity, fair value | 5,133 | 7,750
Collateralized Mortgage Obligations Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 20,199 | 21,519
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 5,121 | 4,163
Securities available for sale | 15,078 | 17,356
Securities held to maturity, Amortized Cost | 14,981 | 17,712
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 1,376 | 1,253
Securities held to maturity, fair value | 13,605 | 16,459
Collateralized Mortgage Obligations Mortgage-Backed Securities, Issued by Private Enterprises [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 0 | 0
Securities available for sale, Unrealized Gains | 325 | 337
Securities available for sale, Unrealized Losses | 0 | 0
Securities available for sale | 325 | 337
Collateralized Mortgage-Backed Securities Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 381,764 | 410,829
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 81,037 | 68,608
Securities available for sale | 300,727 | 342,221
Securities held to maturity, Amortized Cost | 7,686 | 7,959
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 1,695 | 1,396
Securities held to maturity, fair value | $ 5,991 | $ 6,563

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