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SECURITIES - Securities Held to Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
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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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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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.

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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.

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Amount of investment in held-to-maturity debt securities with a single maturity date, after other than temporary impairment (OTTI) accretion.

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