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SECURITIES - Securities Held to Maturity (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
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Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Securities held to maturity, estimated fair value of $4,190 at September 30, 2018 and $3,776 at December 31, 2017 | $ 4,203 | $ 3,781
Unrealized Gains | 0 | 0
Unrealized Losses | 13 | 5
Securities held to maturity | 4,190 | 3,776
Amortized Cost [Abstract] |  |
Within one year | 1,785 |
After one, but within five years | 2,185 |
After five, but within ten years | 233 |
After ten years | 0 |
Total | 4,203 |
Securities held to maturity, estimated fair value of $4,190 at September 30, 2018 and $3,776 at December 31, 2017 | 4,203 | 3,781
Fair Value [Abstract] |  |
Within one year | 1,781 |
After one, but within five years | 2,176 |
After five, but within ten years | 233 |
After ten years | 0 |
Total | 4,190 |
Securities held to maturity | 4,190 | 3,776
Obligations of states and political subdivisions |  |
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Securities held to maturity, estimated fair value of $4,190 at September 30, 2018 and $3,776 at December 31, 2017 | 2,123 | 1,946
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Securities held to maturity | 2,123 | 1,946
Amortized Cost [Abstract] |  |
Securities held to maturity, estimated fair value of $4,190 at September 30, 2018 and $3,776 at December 31, 2017 | 2,123 | 1,946
Fair Value [Abstract] |  |
Securities held to maturity | 2,123 | 1,946
Time deposits with other financial institutions |  |
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Securities held to maturity, estimated fair value of $4,190 at September 30, 2018 and $3,776 at December 31, 2017 | 2,080 | 1,835
Unrealized Gains | 0 | 0
Unrealized Losses | 13 | 5
Securities held to maturity | 2,067 | 1,830
Amortized Cost [Abstract] |  |
Securities held to maturity, estimated fair value of $4,190 at September 30, 2018 and $3,776 at December 31, 2017 | 2,080 | 1,835
Fair Value [Abstract] |  |
Securities held to maturity | 2,067 | $ 1,830
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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- Definition Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.6) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
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- Definition Fair value of held-to-maturity debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. 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 5 -Subparagraph (f)(3) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62586-112803 + Details
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- Definition Fair value of held-to-maturity debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. 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 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62586-112803 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + Details
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- Definition Fair value of held-to-maturity debt securities maturing after the tenth fiscal year following the latest fiscal year. 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 5 -Subparagraph (f)(4) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62586-112803 + Details
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