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SECURITIES - Securities Available for Sale (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |  |  |
Amortized Cost | $ 268,231 |  | $ 268,231 |  | $ 248,496
Unrealized Gains | 2,477 |  | 2,477 |  | 226
Unrealized Losses | 1,422 |  | 1,422 |  | 6,464
Estimated Fair Value | 269,286 |  | 269,286 |  | 242,258
Amortized Cost [Abstract] |  |  |  |  |
Within one year | 8,167 |  | 8,167 |  |
After one, but within five years | 6,465 |  | 6,465 |  |
After five, but within ten years | 34,706 |  | 34,706 |  |
After ten years | 1,104 |  | 1,104 |  |
Total | 50,442 |  | 50,442 |  |
Amortized Cost | 268,231 |  | 268,231 |  | 248,496
Fair Value [Abstract] |  |  |  |  |
Within one year | 8,169 |  | 8,169 |  |
After one, but within five years | 6,609 |  | 6,609 |  |
After five, but within ten years | 35,759 |  | 35,759 |  |
After ten years | 1,124 |  | 1,124 |  |
Total | 51,661 |  | 51,661 |  |
Estimated Fair Value | 269,286 |  | 269,286 |  | 242,258
Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract] |  |  |  |  |
Proceeds | 15,200 | $ 0 | 15,200 | $ 0 |
Gross gains | 79 | 0 | 79 | 0 |
Gross losses | (60) | 0 | (60) | 0 |
Tax expense | 5 | $ 0 | 5 | $ 0 |
Obligations of U.S. Government and U.S. Government sponsored enterprises |  |  |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |  |  |
Amortized Cost | 4,999 |  | 4,999 |  | 5,489
Unrealized Gains | 0 |  | 0 |  | 10
Unrealized Losses | 4 |  | 4 |  | 27
Estimated Fair Value | 4,995 |  | 4,995 |  | 5,472
Amortized Cost [Abstract] |  |  |  |  |
Amortized Cost | 4,999 |  | 4,999 |  | 5,489
Fair Value [Abstract] |  |  |  |  |
Estimated Fair Value | 4,995 |  | 4,995 |  | 5,472
Mortgage-backed securities, residential |  |  |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |  |  |
Amortized Cost | 200,665 |  | 200,665 |  | 189,111
Unrealized Gains | 1,101 |  | 1,101 |  | 146
Unrealized Losses | 1,378 |  | 1,378 |  | 6,065
Estimated Fair Value | 200,388 |  | 200,388 |  | 183,192
Amortized Cost [Abstract] |  |  |  |  |
Without single maturity date | 200,665 |  | 200,665 |  |
Amortized Cost | 200,665 |  | 200,665 |  | 189,111
Fair Value [Abstract] |  |  |  |  |
Without single maturity date | 200,388 |  | 200,388 |  |
Estimated Fair Value | 200,388 |  | 200,388 |  | 183,192
Obligations of states and political subdivisions |  |  |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |  |  |
Amortized Cost | 45,194 |  | 45,194 |  | 44,390
Unrealized Gains | 1,227 |  | 1,227 |  | 70
Unrealized Losses | 5 |  | 5 |  | 308
Estimated Fair Value | 46,416 |  | 46,416 |  | 44,152
Amortized Cost [Abstract] |  |  |  |  |
Amortized Cost | 45,194 |  | 45,194 |  | 44,390
Fair Value [Abstract] |  |  |  |  |
Estimated Fair Value | 46,416 |  | 46,416 |  | 44,152
Corporate bonds and notes |  |  |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |  |  |
Amortized Cost | 249 |  | 249 |  | 249
Unrealized Gains | 1 |  | 1 |  | 0
Unrealized Losses | 0 |  | 0 |  | 2
Estimated Fair Value | 250 |  | 250 |  | 247
Amortized Cost [Abstract] |  |  |  |  |
Amortized Cost | 249 |  | 249 |  | 249
Fair Value [Abstract] |  |  |  |  |
Estimated Fair Value | 250 |  | 250 |  | 247
SBA loan pools |  |  |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |  |  |
Amortized Cost | 17,124 |  | 17,124 |  | 9,257
Unrealized Gains | 148 |  | 148 |  | 0
Unrealized Losses | 35 |  | 35 |  | 62
Estimated Fair Value | 17,237 |  | 17,237 |  | 9,195
Amortized Cost [Abstract] |  |  |  |  |
Without single maturity date | 17,124 |  | 17,124 |  |
Amortized Cost | 17,124 |  | 17,124 |  | 9,257
Fair Value [Abstract] |  |  |  |  |
Without single maturity date | 17,237 |  | 17,237 |  |
Estimated Fair Value | $ 17,237 |  | $ 17,237 |  | $ 9,195

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