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Investment Securities (Amortized Cost And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
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Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Amortized Cost | $ 389,845 | $ 455,582
Securities available for sale, Unrealized Gains | 6,528 | 845
Securities available for sale, Unrealized Losses | 932 | 10,750
Securities available for sale | 395,441 | 445,677
Securities held to maturity, Amortized Cost | 386,305 | 446,581
Securities held to maturity, Unrealized Gains | 4,942 | 899
Securities held to maturity, Unrealized Losses | 761 | 7,899
Securities held to maturity, fair value | 390,486 | 439,581
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 | 71,522 | 155,102
Securities available for sale, Unrealized Gains | 1,288 |
Securities available for sale, Unrealized Losses | 14 | 3,074
Securities available for sale | 72,796 | 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 | 197,743 | 234,845
Securities held to maturity, Unrealized Gains | 3,529 | 876
Securities held to maturity, Unrealized Losses | 5 | 1,211
Securities held to maturity, fair value | 201,267 | 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 | 9,269 | 133
Securities available for sale, Unrealized Losses | 34 |
Securities available for sale | 9,235 | 133
Securities held to maturity, Amortized Cost | 53,179 | 62,103
Securities held to maturity, Unrealized Gains | 228 | 1
Securities held to maturity, Unrealized Losses | 330 | 2,179
Securities held to maturity, fair value | 53,077 | 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 | 5,016 | 37
Securities available for sale, Unrealized Losses | 17 |
Securities available for sale | 4,999 | 37
Securities held to maturity, Amortized Cost | 67,548 | 78,200
Securities held to maturity, Unrealized Gains | 444 |
Securities held to maturity, Unrealized Losses | 261 | 2,597
Securities held to maturity, fair value | 67,731 | 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 | 14,905 | 17,798
Securities held to maturity, Unrealized Gains | 42 |
Securities held to maturity, Unrealized Losses | 98 | 535
Securities held to maturity, fair value | 14,849 | 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 | 658 | 767
Securities available for sale | 658 | 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 | 318,323 | 300,480
Securities available for sale, Unrealized Gains | 5,240 | 845
Securities available for sale, Unrealized Losses | 918 | 7,676
Securities available for sale | 322,645 | 293,649
Securities held to maturity, Amortized Cost | 188,562 | 211,736
Securities held to maturity, Unrealized Gains | 1,413 | 23
Securities held to maturity, Unrealized Losses | 756 | 6,688
Securities held to maturity, fair value | 189,219 | 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 | 264,435 | 258,984
Securities available for sale, Unrealized Gains | 4,100 | 44
Securities available for sale, Unrealized Losses | 688 | 6,325
Securities available for sale | 267,847 | 252,703
Securities held to maturity, Amortized Cost | 10,798 | 11,602
Securities held to maturity, Unrealized Gains | 229 | 8
Securities held to maturity, Unrealized Losses | 1 | 261
Securities held to maturity, fair value | 11,026 | 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 | 35,080 | 35,962
Securities available for sale, Unrealized Gains | 412 | 13
Securities available for sale, Unrealized Losses | 179 | 1,275
Securities available for sale | 35,313 | 34,700
Securities held to maturity, Amortized Cost | 4,048 | 4,583
Securities held to maturity, Unrealized Gains | 95 |
Securities held to maturity, Unrealized Losses | 26 | 193
Securities held to maturity, fair value | 4,117 | 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 | 4,523 | 5,364
Securities available for sale, Unrealized Gains | 70 | 21
Securities available for sale, Unrealized Losses |  | 76
Securities available for sale | 4,593 | 5,309
Securities held to maturity, Amortized Cost | 38,084 | 37,450
Securities held to maturity, Unrealized Gains | 375 | 14
Securities held to maturity, Unrealized Losses | 40 | 923
Securities held to maturity, fair value | $ 38,419 | $ 36,541

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