LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Loans Individually and Collectively Evaluated for Impairment and Respective Allowance for Loan Losses (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	$ 8,673
Unpaid Principal Balance, With related allowance recorded	13,004
Unpaid Principal Balance	21,677
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	8,673
Recorded Investment, With related allowance recorded	13,004
Recorded Investment, With related allowance recorded	21,677
Related Allowance [Abstract]
Related Allowance	1,649
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	7,803
Average Recorded Investment, With related allowance recorded	9,385
Average Recorded Investment, With related allowance recorded	17,188
Commercial and industrial
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	289
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	289
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	312
Average Recorded Investment, With related allowance recorded	61
Construction and development
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	1,212
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	1,212
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	1,259
Commercial real estate
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	4,612
Unpaid Principal Balance, With related allowance recorded	12,871
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	4,612
Recorded Investment, With related allowance recorded	12,871
Related Allowance [Abstract]
Related Allowance	1,587
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	4,244
Average Recorded Investment, With related allowance recorded	9,111
Farmland
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With related allowance recorded	133
Recorded Investment [Abstract]
Recorded Investment, With related allowance recorded	133
Related Allowance [Abstract]
Related Allowance	62
Average Recorded Investment [Abstract]
Average Recorded Investment, With related allowance recorded	135
1-4 family residential
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	2,498
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	2,498
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	1,798
Average Recorded Investment, With related allowance recorded	78
Agricultural
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	62
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	62
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	$ 190

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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