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SECURITIES - Securities Held to Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Amortized Cost	$ 3,865	$ 4,705
Unrealized Gains	1	207
Unrealized Losses	5	0
Securities held to maturity	3,861	4,912
Amortized Cost [Abstract]
Within one year	753
After one, but within five years	2,841
After five, but within ten years	271
After ten years	0
Total	3,865
Fair Value [Abstract]
Within one year	751
After one, but within five years	2,839
After five, but within ten years	271
After ten years	0
Total	3,861
Obligations of states and political subdivisions
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Amortized Cost	2,030	3,725
Unrealized Gains	0	206
Unrealized Losses	0	0
Securities held to maturity	2,030	3,931
Time deposits with other financial institutions
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Amortized Cost	1,835	980
Unrealized Gains	1	1
Unrealized Losses	5	0
Securities held to maturity	$ 1,831	$ 981

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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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