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SECURITIES - Securities Available for Sale (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
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Amortized cost and estimated fair value of securities available for sale [Abstract] |  |
Amortized Cost | $ 269,529 | $ 248,496
Unrealized Gains | 911 | 226
Unrealized Losses | 3,719 | 6,464
Estimated Fair Value | 266,721 | 242,258
Amortized Cost [Abstract] |  |
Within one year | 11,600 |
After one, but within five years | 13,500 |
After five, but within ten years | 26,902 |
After ten years | 1,473 |
Total | 53,475 |
Amortized Cost | 269,529 | 248,496
Fair Value [Abstract] |  |
Within one year | 11,592 |
After one, but within five years | 13,590 |
After five, but within ten years | 27,402 |
After ten years | 1,485 |
Total | 54,069 |
Estimated Fair Value | 266,721 | 242,258
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 | 5,492 | 5,489
Unrealized Gains | 9 | 10
Unrealized Losses | 13 | 27
Estimated Fair Value | 5,488 | 5,472
Amortized Cost [Abstract] |  |
Amortized Cost | 5,492 | 5,489
Fair Value [Abstract] |  |
Estimated Fair Value | 5,488 | 5,472
Mortgage-backed securities, residential |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |
Amortized Cost | 207,277 | 189,111
Unrealized Gains | 283 | 146
Unrealized Losses | 3,622 | 6,065
Estimated Fair Value | 203,938 | 183,192
Amortized Cost [Abstract] |  |
Without single maturity date | 207,277 |
Amortized Cost | 207,277 | 189,111
Fair Value [Abstract] |  |
Without single maturity date | 203,938 |
Estimated Fair Value | 203,938 | 183,192
Obligations of states and political subdivisions |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |
Amortized Cost | 47,733 | 44,390
Unrealized Gains | 619 | 70
Unrealized Losses | 20 | 308
Estimated Fair Value | 48,332 | 44,152
Amortized Cost [Abstract] |  |
Amortized Cost | 47,733 | 44,390
Fair Value [Abstract] |  |
Estimated Fair Value | 48,332 | 44,152
Corporate bonds and notes |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |
Amortized Cost | 250 | 249
Unrealized Gains | 0 | 0
Unrealized Losses | 1 | 2
Estimated Fair Value | 249 | 247
Amortized Cost [Abstract] |  |
Amortized Cost | 250 | 249
Fair Value [Abstract] |  |
Estimated Fair Value | 249 | 247
SBA loan pools |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |
Amortized Cost | 8,777 | 9,257
Unrealized Gains | 0 | 0
Unrealized Losses | 63 | 62
Estimated Fair Value | 8,714 | 9,195
Amortized Cost [Abstract] |  |
Without single maturity date | 8,777 |
Amortized Cost | 8,777 | 9,257
Fair Value [Abstract] |  |
Without single maturity date | 8,714 |
Estimated Fair Value | $ 8,714 | $ 9,195

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