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SECURITIES - Securities Available for Sale (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |
Amortized Cost | $ 298,212 | $ 310,401 |
Estimated Fair Value | 293,627 | 303,402 |
Unrealized Gains | 785 | 806 |
Unrealized Losses | 5,370 | 7,805 |
Amortized Cost |  |  |
Within one year | 16,998 |  |
After one, but within five years | 21,048 |  |
After five, but within ten years | 12,700 |  |
After ten years | 17,923 |  |
Total | 297,947 |  |
Fair Value |  |  |
Within one year | 16,990 |  |
After one, but within five years | 21,074 |  |
After five, but within ten years | 12,746 |  |
After ten years | 18,064 |  |
Total | 293,091 |  |
Proceeds from sales and calls of securities resulting in gains or losses [Abstract] |  |  |
Proceeds | 5,576 | 40,413 | $ 72,718
Gross gains | 109 | 989 | 410
Gross losses | 0 | (2) | (38)
Tax expense | 41 | 373 | $ 142
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 | 15,492 | 17,300 |
Estimated Fair Value | 15,491 | 17,455 |
Unrealized Gains | 20 | 155 |
Unrealized Losses | 21 | 0 |
Mortgage-backed securities, residential |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |
Amortized Cost | 224,939 | 253,156 |
Estimated Fair Value | 219,909 | 245,866 |
Unrealized Gains | 136 | 202 |
Unrealized Losses | 5,166 | 7,492 |
Amortized Cost |  |  |
Without single maturity date | 224,939 |  |
Fair Value |  |  |
Without single maturity date | 219,909 |  |
Obligations of states and political subdivisions |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |
Amortized Cost | 52,928 | 38,843 |
Estimated Fair Value | 53,132 | 38,740 |
Unrealized Gains | 355 | 209 |
Unrealized Losses | 151 | 312 |
Corporate bonds and notes |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |
Amortized Cost | 249 | 249 |
Estimated Fair Value | 251 | 250 |
Unrealized Gains | 2 | 1 |
Unrealized Losses | 0 | 0 |
SBA loan pools |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |
Amortized Cost | 4,339 | 568 |
Estimated Fair Value | 4,308 | 570 |
Unrealized Gains | 1 | 3 |
Unrealized Losses | 32 | 1 |
Amortized Cost |  |  |
Without single maturity date | 4,339 |  |
Fair Value |  |  |
Without single maturity date | 4,308 |  |
Corporate stocks |  |  |
Amortized cost and estimated fair value of securities available for sale [Abstract] |  |  |
Amortized Cost | 265 | 285 |
Estimated Fair Value | 536 | 521 |
Unrealized Gains | 271 | 236 |
Unrealized Losses | $ 0 | $ 0 |

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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 + Details
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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