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Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | $ 1,103,851 | $ 1,127,057
Securities available for sale, Unrealized Gains | 343 | 338
Securities available for sale, Unrealized Losses | 158,752 | 173,024
Securities available for sale | 945,442 | 954,371
Securities held to maturity, Amortized Cost | 180,057 | 188,980
Securities held to maturity, Unrealized Gains | 32 | 24
Securities held to maturity, Unrealized Losses | 12,277 | 14,816
Securities held to maturity, fair value | 167,812 | 174,188
Allowance for credit losses, Amortized Cost | (5) | (5)
Held-to-maturity securities, net , Amortized Cost | 180,052 | 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 | 2,877 | 3,420
Securities available for sale | 21,658 | 21,115
Securities held to maturity, Amortized Cost | 16,400 | 16,363
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 544 | 848
Securities held to maturity, fair value | 15,856 | 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 | 93,678 | 97,583
Securities held to maturity, Unrealized Gains | 32 | 24
Securities held to maturity, Unrealized Losses | 6,012 | 7,172
Securities held to maturity, fair value | 87,698 | 90,435
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 | 536,221 | 545,797
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 68,817 | 76,193
Securities available for sale | 467,404 | 469,604
Securities held to maturity, Amortized Cost | 6,038 | 8,332
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 457 | 582
Securities held to maturity, fair value | 5,581 | 7,750
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 | 398,487 | 410,829
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 62,373 | 68,608
Securities available for sale | 336,114 | 342,221
Securities held to maturity, Amortized Cost | 7,786 | 7,959
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 1,256 | 1,396
Securities held to maturity, fair value | 6,530 | 6,563
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 | 111,527 | 112,202
Securities available for sale, Unrealized Gains | 1 | 1
Securities available for sale, Unrealized Losses | 18,295 | 18,037
Securities available for sale | 93,233 | 94,166
Securities held to maturity, Amortized Cost | 21,783 | 22,541
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 1,723 | 2,116
Securities held to maturity, fair value | 20,060 | 20,425
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 | 11,938 | 12,175
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 2,326 | 2,603
Securities available for sale | 9,612 | 9,572
Securities held to maturity, Amortized Cost | 13,536 | 14,268
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 963 | 1,119
Securities held to maturity, fair value | 12,573 | 13,149
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 | 21,143 | 21,519
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 4,064 | 4,163
Securities available for sale | 17,079 | 17,356
Securities held to maturity, Amortized Cost | 16,781 | 17,712
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 1,022 | 1,253
Securities held to maturity, fair value | 15,759 | 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 | 342 | 337
Securities available for sale, Unrealized Losses | 0 | 0
Securities available for sale | 342 | 337
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 | 4,055 | 4,222
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 300 | 330
Securities held to maturity, fair value | 3,755 | 3,892
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 1,079,316 | 1,102,522
Securities available for sale, Unrealized Gains | 343 | 338
Securities available for sale, Unrealized Losses | 155,875 | 169,604
Securities available for sale | 923,784 | 933,256
Securities held to maturity, Amortized Cost | 69,979 | 75,034
Securities held to maturity, Unrealized Gains | 0 | 0
Securities held to maturity, Unrealized Losses | 5,721 | 6,796
Securities held to maturity, fair value | $ 64,258 | $ 68,238

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