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SECURITIES - Securities Held to Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Amortized Cost	$ 2,453	$ 2,469
Unrecognized Gains	29	32
Unrecognized Losses	0	0
Estimated Fair Value	2,482	2,501
Amortized Cost [Abstract]
Within one year	1,064
After one, but within five years	1,389
After five, but within ten years	0
After ten years	0
Total	2,453
Securities held to maturity	2,453	2,469
Fair Value [Abstract]
Within one year	1,074
After one, but within five years	1,408
After five, but within ten years	0
After ten years	0
Total	2,482
Securities held to maturity	2,482	2,501
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]
Amortized Cost	316	326
Unrecognized Gains	0	0
Unrecognized Losses	0	0
Estimated Fair Value	316	326
Amortized Cost [Abstract]
Securities held to maturity	316	326
Fair Value [Abstract]
Securities held to maturity	316	326
Time deposits with other financial institutions
Amortized cost and estimated fair value of securities held to maturity [Abstract]
Amortized Cost	2,137	2,143
Unrecognized Gains	29	32
Unrecognized Losses	0	0
Estimated Fair Value	2,166	2,175
Amortized Cost [Abstract]
Securities held to maturity	2,137	2,143
Fair Value [Abstract]
Securities held to maturity	2,166	$ 2,175
SBA loan pools
Amortized Cost [Abstract]
Without single maturity date	0
Fair Value [Abstract]
Without single maturity date	$ 0

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