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Investment Securities (Investments Gross Unrealized Losses and Fair Value) (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 19,752 | $ 129,206
Securities available for sale, Less than 12 months, Unrealized Losses | 466 | 1,367
Securities available for sale, 12 months or longer, Fair Value | 8 | 16,613
Securities available for sale, 12 months or longer, Unrealized Losses |  | 264
Securities available for sale, Fair Value, Total | 19,760 | 145,819
Securities available for sale, Unrealized Losses, Total | 466 | 1,631
Securities held to maturity, Less than 12 months, Fair Value |  | 49,517
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 228
Securities held to maturity, 12 months or longer, Fair Value |  | 30,589
Securities held to maturity, 12 months or longer, Unrealized Losses |  | 395
Securities held to maturity, Fair Value, Total |  | 80,106
Securities held to maturity, Unrealized Losses, Total | 3 | 623
Total Securities, Less than 12 months, Fair Value | 19,752 | 178,723
Total Securities, Less than 12 months, Unrealized Losses | 466 | 1,595
Total Securities, 12 months or longer, Fair Value | 8 | 47,202
Total Securities, 12 months or longer, Unrealized Losses |  | 659
Total Securities, Fair Value | 19,760 | 225,925
Total Securities, Unrealized Losses | 466 | 2,254
State And Political Subdivisions [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities held to maturity, Unrealized Losses, Total | 3 |
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, Less than 12 months, Fair Value | 3,808 | 8,803
Securities available for sale, Less than 12 months, Unrealized Losses | 36 | 57
Securities available for sale, 12 months or longer, Fair Value | 8 | 8
Securities available for sale, Fair Value, Total | 3,816 | 8,811
Securities available for sale, Unrealized Losses, Total | 36 | 57
Securities held to maturity, Less than 12 months, Fair Value |  | 9,120
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 40
Securities held to maturity, 12 months or longer, Fair Value |  | 13,486
Securities held to maturity, 12 months or longer, Unrealized Losses |  | 216
Securities held to maturity, Fair Value, Total |  | 22,606
Securities held to maturity, Unrealized Losses, Total |  | 256
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, Less than 12 months, Fair Value | 4,761 | 4,889
Securities available for sale, Less than 12 months, Unrealized Losses | 48 | 18
Securities available for sale, 12 months or longer, Fair Value |  | 0
Securities available for sale, Fair Value, Total | 4,761 | 4,889
Securities available for sale, Unrealized Losses, Total | 48 | 18
Securities held to maturity, Less than 12 months, Fair Value |  | 15,127
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 30
Securities held to maturity, 12 months or longer, Fair Value |  | 7,988
Securities held to maturity, 12 months or longer, Unrealized Losses |  | 73
Securities held to maturity, Fair Value, Total |  | 23,115
Securities held to maturity, Unrealized Losses, Total |  | 103
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, Less than 12 months, Fair Value |  | 8,760
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 72
Securities held to maturity, 12 months or longer, Fair Value |  | 892
Securities held to maturity, 12 months or longer, Unrealized Losses |  | 11
Securities held to maturity, Fair Value, Total |  | 9,652
Securities held to maturity, Unrealized Losses, Total |  | 83
Mortgage-Backed Securities [Member] |  |
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item] |  |
Securities available for sale, Less than 12 months, Fair Value | 19,752 | 129,206
Securities available for sale, Less than 12 months, Unrealized Losses | 466 | 1,367
Securities available for sale, 12 months or longer, Fair Value | 8 | 16,613
Securities available for sale, 12 months or longer, Unrealized Losses |  | 264
Securities available for sale, Fair Value, Total | 19,760 | 145,819
Securities available for sale, Unrealized Losses, Total | 466 | 1,631
Securities held to maturity, Less than 12 months, Fair Value |  | 49,517
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 228
Securities held to maturity, 12 months or longer, Fair Value |  | 30,589
Securities held to maturity, 12 months or longer, Unrealized Losses |  | 395
Securities held to maturity, Fair Value, Total |  | 80,106
Securities held to maturity, Unrealized Losses, Total |  | 623
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, Less than 12 months, Fair Value | 5,502 | 104,634
Securities available for sale, Less than 12 months, Unrealized Losses | 217 | 1,277
Securities available for sale, 12 months or longer, Fair Value |  | 7,196
Securities available for sale, 12 months or longer, Unrealized Losses |  | 103
Securities available for sale, Fair Value, Total | 5,502 | 111,830
Securities available for sale, Unrealized Losses, Total | 217 | 1,380
Securities held to maturity, Less than 12 months, Fair Value |  | 2,388
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 6
Securities held to maturity, Fair Value, Total |  | 2,388
Securities held to maturity, Unrealized Losses, Total |  | 6
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, Less than 12 months, Fair Value |  | 10,347
Securities available for sale, Less than 12 months, Unrealized Losses |  | 11
Securities available for sale, 12 months or longer, Fair Value |  | 9,409
Securities available for sale, 12 months or longer, Unrealized Losses |  | 161
Securities available for sale, Fair Value, Total |  | 19,756
Securities available for sale, Unrealized Losses, Total |  | 172
Securities held to maturity, Less than 12 months, Fair Value |  | 2,967
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 19
Securities held to maturity, 12 months or longer, Fair Value |  | 2,598
Securities held to maturity, 12 months or longer, Unrealized Losses |  | 28
Securities held to maturity, Fair Value, Total |  | 5,565
Securities held to maturity, Unrealized Losses, Total |  | 47
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, Less than 12 months, Fair Value | 5,681 | 533
Securities available for sale, Less than 12 months, Unrealized Losses | 165 | 4
Securities available for sale, Fair Value, Total | 5,681 | 533
Securities available for sale, Unrealized Losses, Total | $ 165 | 4
Securities held to maturity, Less than 12 months, Fair Value |  | 11,155
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 61
Securities held to maturity, 12 months or longer, Fair Value |  | 5,625
Securities held to maturity, 12 months or longer, Unrealized Losses |  | 67
Securities held to maturity, Fair Value, Total |  | 16,780
Securities held to maturity, Unrealized Losses, Total |  | $ 128

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