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Investment Securities (Amortized Cost And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | $ 415,852 | $ 455,582
Securities available for sale, Unrealized Gains | 3,696 | 845
Securities available for sale, Unrealized Losses | 1,631 | 10,750
Securities available for sale | 417,917 | 445,677
Securities held to maturity, Amortized Cost | 359,000 | 446,581
Securities held to maturity, Unrealized Gains | 4,882 | 899
Securities held to maturity, Unrealized Losses | 623 | 7,899
Securities held to maturity, fair value | 363,259 | 439,581
U.S. Government Agencies 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 | 26,440 | 155,102
Securities available for sale, Unrealized Gains | 437 |
Securities available for sale, Unrealized Losses |  | 3,074
Securities available for sale | 26,877 | 152,028
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 | 192,215 | 234,845
Securities held to maturity, Unrealized Gains | 3,803 | 876
Securities held to maturity, Unrealized Losses |  | 1,211
Securities held to maturity, fair value | 196,018 | 234,510
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 | 23,834 | 133
Securities available for sale, Unrealized Losses | 57 |
Securities available for sale | 23,777 | 133
Securities held to maturity, Amortized Cost | 41,561 | 62,103
Securities held to maturity, Unrealized Gains | 150 | 1
Securities held to maturity, Unrealized Losses | 256 | 2,179
Securities held to maturity, fair value | 41,455 | 59,925
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 | 4,907 | 37
Securities available for sale, Unrealized Losses | 18 |
Securities available for sale | 4,889 | 37
Securities held to maturity, Amortized Cost | 49,389 | 78,200
Securities held to maturity, Unrealized Gains | 307 |
Securities held to maturity, Unrealized Losses | 103 | 2,597
Securities held to maturity, fair value | 49,593 | 75,603
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 | 11,033 | 17,798
Securities held to maturity, Unrealized Gains | 12 |
Securities held to maturity, Unrealized Losses | 83 | 535
Securities held to maturity, fair value | 10,962 | 17,263
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 | 618 | 767
Securities available for sale | 618 | 767
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | 389,412 | 300,480
Securities available for sale, Unrealized Gains | 3,259 | 845
Securities available for sale, Unrealized Losses | 1,631 | 7,676
Securities available for sale | 391,040 | 293,649
Securities held to maturity, Amortized Cost | 166,785 | 211,736
Securities held to maturity, Unrealized Gains | 1,079 | 23
Securities held to maturity, Unrealized Losses | 623 | 6,688
Securities held to maturity, fair value | 167,241 | 205,071
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 | 293,873 | 258,984
Securities available for sale, Unrealized Gains | 2,263 | 44
Securities available for sale, Unrealized Losses | 1,380 | 6,325
Securities available for sale | 294,756 | 252,703
Securities held to maturity, Amortized Cost | 12,049 | 11,602
Securities held to maturity, Unrealized Gains | 227 | 8
Securities held to maturity, Unrealized Losses | 6 | 261
Securities held to maturity, fair value | 12,270 | 11,349
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 | 52,733 | 35,962
Securities available for sale, Unrealized Gains | 318 | 13
Securities available for sale, Unrealized Losses | 172 | 1,275
Securities available for sale | 52,879 | 34,700
Securities held to maturity, Amortized Cost | 6,995 | 4,583
Securities held to maturity, Unrealized Gains | 77 |
Securities held to maturity, Unrealized Losses | 47 | 193
Securities held to maturity, fair value | 7,025 | 4,390
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 | 14,065 | 5,364
Securities available for sale, Unrealized Gains | 60 | 21
Securities available for sale, Unrealized Losses | 4 | 76
Securities available for sale | 14,121 | 5,309
Securities held to maturity, Amortized Cost | 45,758 | 37,450
Securities held to maturity, Unrealized Gains | 306 | 14
Securities held to maturity, Unrealized Losses | 128 | 923
Securities held to maturity, fair value | $ 45,936 | $ 36,541

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