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Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | $ 1,183,305 | $ 1,184,835
Securities available for sale, Unrealized Gains | 370 | 8,446
Securities available for sale, Unrealized Losses | 126,657 | 14,766
Securities available for sale | 1,057,018 | 1,178,515
Securities held to maturity, Amortized Cost | 204,938 | 205,586
Securities held to maturity, Unrealized Gains | 111 | 4,683
Securities held to maturity, Unrealized Losses | 9,598 | 449
Securities held to maturity, fair value | 195,451 | 209,820
Allowance for credit losses, Amortized Cost | (5) | (5)
Held-to-maturity securities, net , Amortized Cost | 204,933 | 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 | 2,345 | 97
Securities available for sale | 22,190 | 15,891
Securities held to maturity, Amortized Cost | 16,288 |
Securities held to maturity, Unrealized Losses | 105 |
Securities held to maturity, fair value | 16,183 |
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 | 105,978 | 111,399
Securities held to maturity, Unrealized Gains | 106 | 2,412
Securities held to maturity, Unrealized Losses | 5,618 | 300
Securities held to maturity, fair value | 100,466 | 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, Amortized Cost | 13,188 | 15,346
Securities available for sale, Unrealized Gains | 0 | 26
Securities available for sale, Unrealized Losses | 1,770 | 433
Securities available for sale | 11,418 | 14,939
Securities held to maturity, Amortized Cost | 16,312 | 19,485
Securities held to maturity, Unrealized Gains |  | 368
Securities held to maturity, Unrealized Losses | 619 | 3
Securities held to maturity, fair value | 15,693 | 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, Amortized Cost | 22,734 | 25,257
Securities available for sale, Unrealized Gains | 0 | 0
Securities available for sale, Unrealized Losses | 2,773 | 477
Securities available for sale | 19,961 | 24,780
Securities held to maturity, Amortized Cost | 20,100 | 23,840
Securities held to maturity, Unrealized Gains | 0 | 565
Securities held to maturity, Unrealized Losses | 638 | 0
Securities held to maturity, fair value | 19,462 | 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 | 4,698 | 5,481
Securities held to maturity, Unrealized Gains | 0 | 84
Securities held to maturity, Unrealized Losses | 171 | 0
Securities held to maturity, fair value | 4,527 | 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, Amortized Cost | 0 | 0
Securities available for sale, Unrealized Gains | 365 | 410
Securities available for sale, Unrealized Losses | 0 | 0
Securities available for sale | 365 | 410
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 1,158,770 | 1,169,042
Securities available for sale, Unrealized Gains | 370 | 8,251
Securities available for sale, Unrealized Losses | 124,312 | 14,669
Securities available for sale | 1,034,828 | 1,162,624
Securities held to maturity, Amortized Cost | 82,672 | 94,187
Securities held to maturity, Unrealized Gains | 5 | 2,271
Securities held to maturity, Unrealized Losses | 3,875 | 149
Securities held to maturity, fair value | 78,802 | 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, Amortized Cost | 575,815 | 576,163
Securities available for sale, Unrealized Gains | 2 | 6,565
Securities available for sale, Unrealized Losses | 54,832 | 5,242
Securities available for sale | 520,985 | 577,486
Securities held to maturity, Amortized Cost | 8,844 | 9,275
Securities held to maturity, Unrealized Gains | 4 | 411
Securities held to maturity, Unrealized Losses | 305 | 0
Securities held to maturity, fair value | 8,543 | 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, Amortized Cost | 430,099 | 430,010
Securities available for sale, Unrealized Gains | 1 | 952
Securities available for sale, Unrealized Losses | 52,524 | 6,435
Securities available for sale | 377,576 | 424,527
Securities held to maturity, Amortized Cost | 8,077 | 8,706
Securities held to maturity, Unrealized Gains | 0 | 137
Securities held to maturity, Unrealized Losses | 986 | 144
Securities held to maturity, fair value | 7,091 | 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, Amortized Cost | 116,934 | 122,266
Securities available for sale, Unrealized Gains | 2 | 298
Securities available for sale, Unrealized Losses | 12,413 | 2,082
Securities available for sale | 104,523 | 120,482
Securities held to maturity, Amortized Cost | 24,641 | 27,400
Securities held to maturity, Unrealized Gains | 1 | 706
Securities held to maturity, Unrealized Losses | 1,156 | 2
Securities held to maturity, fair value | $ 23,486 | $ 28,104

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