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SECURITIES - Securities Held to Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Securities held to maturity	$ 3,047	$ 3,115
Unrecognized Gains	46	24
Unrecognized Losses	0	0
Securities held to maturity	3,093	3,139
Amortized Cost [Abstract]
Within one year	609
After one, but within five years	2,438
After five, but within ten years	0
After ten years	0
Total	3,047
Securities held to maturity	3,047	3,115
Fair Value [Abstract]
Within one year	613
After one, but within five years	2,480
After five, but within ten years	0
After ten years	0
Total	3,093
Securities held to maturity	3,093	3,139
Mortgage-backed securities, residential
Amortized Cost [Abstract]
Without single maturity date	0
Fair Value [Abstract]
Without single maturity date	0
Obligations of states and political subdivisions
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Securities held to maturity	409	1,045
Unrecognized Gains	0	0
Unrecognized Losses	0	0
Securities held to maturity	409	1,045
Amortized Cost [Abstract]
Securities held to maturity	409	1,045
Fair Value [Abstract]
Securities held to maturity	409	1,045
Time deposits with other financial institutions
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Securities held to maturity	2,638	2,070
Unrecognized Gains	46	24
Unrecognized Losses	0	0
Securities held to maturity	2,684	2,094
Amortized Cost [Abstract]
Securities held to maturity	2,638	2,070
Fair Value [Abstract]
Securities held to maturity	2,684	$ 2,094
SBA loan pools
Amortized Cost [Abstract]
Without single maturity date	0
Fair Value [Abstract]
Without single maturity date	$ 0

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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