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SECURITIES - Securitites Held to Maturity (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Amortized Cost | $ 3,781,000 | $ 4,705,000
Estimated Fair Value | 3,776,000 | 4,912,000
Unrealized Gains | 0 | 207,000
Unrealized Losses | 5,000 | 0
Amortized Cost |  |
Within one year | 988,000 |
After one, but within five years | 2,560,000 |
After five, but within ten years | 233,000 |
After ten years | 0 |
Total | 3,781,000 | 4,705,000
Fair Value |  |
Within one year | 986,000 |
After one, but within five years | 2,557,000 |
After five, but within ten years | 233,000 |
After ten years | 0 |
Total | 3,776,000 | 4,912,000
Gain (loss) on sale of held-to-maturity securities | 0 | 0
Obligations of states and political subdivisions |  |
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Amortized Cost | 1,946,000 | 3,725,000
Estimated Fair Value | 1,946,000 | 3,931,000
Unrealized Gains | 0 | 206,000
Unrealized Losses | 0 | 0
Amortized Cost |  |
Total | 1,946,000 | 3,725,000
Fair Value |  |
Total | 1,946,000 | 3,931,000
Time deposits with other financial institutions |  |
Amortized cost and estimated fair value of securities held to maturity [Abstract] |  |
Amortized Cost | 1,835,000 | 980,000
Estimated Fair Value | 1,830,000 | 981,000
Unrealized Gains | 0 | 1,000
Unrealized Losses | 5,000 | 0
Amortized Cost |  |
Total | 1,835,000 | 980,000
Fair Value |  |
Total | $ 1,830,000 | $ 981,000

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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 Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the fifth through tenth fiscal year following the latest fiscal year. + 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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