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SECURITIES - Securities Held to Maturity (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Securities held to maturity | $ 3,420 | $ 4,875
Unrealized Gains | 23 | 0
Unrealized Losses | 0 | 17
Securities held to maturity | 3,443 | 4,858
Amortized Cost [Abstract] |  |
Within one year | 1,340 |
After one, but within five years | 2,080 |
After five, but within ten years | 0 |
After ten years | 0 |
Total | 3,420 |
Securities held to maturity | 3,420 | 4,875
Fair Value [Abstract] |  |
Within one year | 1,340 |
After one, but within five years | 2,103 |
After five, but within ten years | 0 |
After ten years | 0 |
Total | 3,443 |
Securities held to maturity | 3,443 | 4,858
Obligations of states and political subdivisions |  |
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Securities held to maturity | 1,125 | 3,020
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Securities held to maturity | 1,125 | 3,020
Amortized Cost [Abstract] |  |
Securities held to maturity | 1,125 | 3,020
Fair Value [Abstract] |  |
Securities held to maturity | 1,125 | 3,020
Time deposits with other financial institutions |  |
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Securities held to maturity | 2,295 | 1,855
Unrealized Gains | 23 | 0
Unrealized Losses | 0 | 17
Securities held to maturity | 2,318 | 1,838
Amortized Cost [Abstract] |  |
Securities held to maturity | 2,295 | 1,855
Fair Value [Abstract] |  |
Securities held to maturity | 2,318 | $ 1,838
Mortgage-backed securities, residential |  |
Amortized Cost [Abstract] |  |
Without single maturity date | 0 |
SBA loan pools |  |
Amortized Cost [Abstract] |  |
Without single maturity date | $ 0 |

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