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Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | $ 1,149,475 | $ 1,184,835
Securities available for sale, Unrealized Gains | 345 | 8,446
Securities available for sale, Unrealized Losses | 184,289 | 14,766
Securities available for sale | 965,531 | 1,178,515
Securities held to maturity, Amortized Cost | 197,543 | 205,586
Securities held to maturity, Unrealized Gains | 16 | 4,683
Securities held to maturity, Unrealized Losses | 17,121 | 449
Securities held to maturity, fair value | 180,438 | 209,820
Allowance for credit losses, Amortized Cost | (5) | (5)
Held-to-maturity securities, net , Amortized Cost | 197,538 | 205,581
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 | 15,793
Securities available for sale, Unrealized Gains | 0 | 195
Securities available for sale, Unrealized Losses | 3,428 | 97
Securities available for sale | 21,107 | 15,891
Securities held to maturity, Amortized Cost | 16,325 |
Securities held to maturity, Unrealized Gains | 0 |
Securities held to maturity, Unrealized Losses | 850 |
Securities held to maturity, fair value | 15,475 |
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 | 102,419 | 111,399
Securities held to maturity, Unrealized Gains | 16 | 2,412
Securities held to maturity, Unrealized Losses | 8,975 | 300
Securities held to maturity, fair value | 93,460 | 113,511
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, Unrealized Gains | 0 | 26
Securities available for sale, Unrealized Losses | 2,489 | 433
Securities held to maturity, Amortized Cost | 8,576 | 19,485
Securities held to maturity, Unrealized Gains | 0 | 368
Securities held to maturity, Unrealized Losses | 1,084 | 3
Securities held to maturity, fair value | 7,918 | 19,850
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, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 4,139 | 477
Securities held to maturity, Amortized Cost |  | 23,840
Securities held to maturity, Unrealized Gains |  | 565
Securities held to maturity, Unrealized Losses | 1,247 | 0
Securities held to maturity, fair value |  | 24,405
Collateralized Mortgage Obligations [Member] | Government National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities held to maturity, Amortized Cost | 4,421 | 5,481
Securities held to maturity, Unrealized Gains | 0 | 84
Securities held to maturity, Unrealized Losses | 314 | 0
Securities held to maturity, fair value | 4,107 | 5,565
Collateralized Mortgage Obligations [Member] | Privately Issued [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Unrealized Gains | 344 | 410
Securities available for sale, Unrealized Losses | 0 | 0
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 1,124,940 | 1,169,042
Securities available for sale, Unrealized Gains | 345 | 8,251
Securities available for sale, Unrealized Losses | 180,861 | 14,669
Securities available for sale | 944,424 | 1,162,624
Securities held to maturity, Amortized Cost | 78,799 | 94,187
Securities held to maturity, Unrealized Gains | 0 | 2,271
Securities held to maturity, Unrealized Losses | 7,296 | 149
Securities held to maturity, fair value | 71,503 | 96,309
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, Unrealized Gains | 0 | 6,565
Securities available for sale, Unrealized Losses | 83,012 | 5,242
Securities held to maturity, Amortized Cost |  | 9,275
Securities held to maturity, Unrealized Gains | 0 | 411
Securities held to maturity, Unrealized Losses | 658 | 0
Securities held to maturity, fair value |  | 9,686
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, Unrealized Gains | 0 | 952
Securities available for sale, Unrealized Losses | 74,634 | 6,435
Securities held to maturity, Amortized Cost | 8,009 | 8,706
Securities held to maturity, Unrealized Gains | 0 | 137
Securities held to maturity, Unrealized Losses | 1,485 | 144
Securities held to maturity, fair value | 6,524 | 8,699
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, Unrealized Gains | 1 |
Securities available for sale, Unrealized Losses | 16,587 | 2,082
Securities held to maturity, Amortized Cost | 23,854 | 27,400
Securities held to maturity, Unrealized Gains | 0 | 706
Securities held to maturity, Unrealized Losses | 2,508 | 2
Securities held to maturity, fair value | 21,346 | 28,104
Collateralized Mortgage-Backed Securities Government National Mortgage Association [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 114,019 |
Securities available for sale | 97,433 |
Collateralized Mortgage-Backed Federal National Mortgage Association Certificates and Obligations [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 556,883 | 576,163
Securities available for sale | 473,871 | 577,486
Collateralized Mortgage-Back Federal Home Loan Mortgage Corporation Certificates and Obligations [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 419,428 | 430,010
Securities available for sale | 344,794 | 424,527
Securities held to maturity, Amortized Cost | 18,749 |
Securities held to maturity, fair value | 17,502 |
Collateralized Mortgage-Backed Government National Mortgage Association Certificates and Obligations [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost |  | 122,266
Securities available for sale, Unrealized Gains |  | 298
Securities available for sale |  | 120,482
Collateralized Federal National Mortgage Association Certificates and Obligation [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 12,569 | 15,346
Securities available for sale | 10,080 | 14,939
Securities held to maturity, Amortized Cost | 15,190 |
Securities held to maturity, fair value | 14,106 |
Collateralized Federal Home Loan Mortgage Corporation Certificates and Obligations [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 22,041 | 25,257
Securities available for sale | 17,902 | 24,780
Collateralized 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 | $ 344 | $ 410

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