FAIR VALUE MEASUREMENTS AND FAIR VALUES OF FINANCIAL INSTRUMENTS - Level 3 Valuation Techniques Nonrecurring (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	$ 8,082,000	$ 3,375,000
Related allowance	925,000	1,051,000
Nonrecurring fair value measurements
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	7,157,000	2,324,000
Related allowance	925,000	1,051,000
Foreclosed assets held for sale	1,338,000	2,886,000
Real estate loan
Valuation Techniques and the Unobservable Inputs
Related allowance	416,000	678,000
Residential mortgage
Valuation Techniques and the Unobservable Inputs
Foreclosed assets held for sale	80,000	292,000
Residential mortgage \| Real estate loan
Valuation Techniques and the Unobservable Inputs
Related allowance	153,000	176,000
Commercial \| Real estate loan
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	6,501,000	0
Related allowance	691,000	0
Commercial \| Commercial and industrial
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	72,000	904,000
Related allowance	72,000	149,000
Commercial \| Loans secured by farm land
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	0	478,000
Related allowance	0	48,000
Impaired Loans
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	8,082,000	3,375,000
Related allowance	925,000	1,051,000
Fair value	7,157,000	2,324,000
Impaired Loans \| Valuation, Market Approach \| Residential mortgage \| Real estate loan
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	1,509,000	732,000
Related allowance	162,000	176,000
Fair value	$ 1,347,000	$ 556,000
Impaired Loans \| Valuation, Market Approach \| Residential mortgage \| Real estate loan \| Weighted average
Valuation Techniques and the Unobservable Inputs
Discount rate	31.00%	30.00%
Impaired Loans \| Valuation, Market Approach \| Commercial \| Real estate loan
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance		$ 478,000
Related allowance		48,000
Fair value		$ 430,000
Impaired Loans \| Valuation, Market Approach \| Commercial \| Real estate loan \| Weighted average
Valuation Techniques and the Unobservable Inputs
Discount rate		46.00%
Impaired Loans \| Valuation, Market Approach \| Commercial \| Commercial and industrial
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	$ 6,501,000	$ 106,000
Related allowance	691,000	89,000
Fair value	5,810,000	17,000
Impaired Loans \| Valuation, Market Approach \| Commercial \| Commercial and industrial \| Measurement Input Discount To Borrowers Financial Statement Value Member
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance	72,000	798,000
Related allowance	72,000	60,000
Fair value		$ 738,000
Fair value	$ 0
Impaired Loans \| Valuation, Market Approach \| Commercial \| Commercial and industrial \| Weighted average
Valuation Techniques and the Unobservable Inputs
Discount rate	28.00%	69.00%
Impaired Loans \| Valuation, Market Approach \| Commercial \| Commercial and industrial \| Weighted average \| Measurement Input Discount To Borrowers Financial Statement Value Member
Valuation Techniques and the Unobservable Inputs
Discount rate	100.00%	15.00%
Impaired Loans \| Valuation, Market Approach \| Commercial \| Loans secured by farm land
Valuation Techniques and the Unobservable Inputs
Recorded investment - with allowance		$ 1,261,000
Related allowance		678,000
Fair value		$ 583,000
Impaired Loans \| Valuation, Market Approach \| Commercial \| Loans secured by farm land \| Weighted average
Valuation Techniques and the Unobservable Inputs
Discount rate		47.00%
Foreclosed Assets Held For Sale
Valuation Techniques and the Unobservable Inputs
Foreclosed assets held for sale	$ 1,338,000	$ 2,886,000
Valuation allowance	0	0
Fair value	1,338,000	2,886,000
Foreclosed Assets Held For Sale \| Valuation, Market Approach \| Land Receivable
Valuation Techniques and the Unobservable Inputs
Foreclosed assets held for sale		70,000
Valuation allowance		0
Fair value		$ 70,000
Foreclosed Assets Held For Sale \| Valuation, Market Approach \| Land Receivable \| Weighted average
Valuation Techniques and the Unobservable Inputs
Discount rate		53.00%
Foreclosed Assets Held For Sale \| Valuation, Market Approach \| Commercial Real Estate Receivables
Valuation Techniques and the Unobservable Inputs
Foreclosed assets held for sale	1,258,000	$ 2,524,000
Valuation allowance	0	0
Fair value	$ 1,258,000	$ 2,524,000
Foreclosed Assets Held For Sale \| Valuation, Market Approach \| Commercial Real Estate Receivables \| Weighted average
Valuation Techniques and the Unobservable Inputs
Discount rate	44.00%	39.00%
Foreclosed Assets Held For Sale \| Valuation, Market Approach \| Residential mortgage
Valuation Techniques and the Unobservable Inputs
Foreclosed assets held for sale	$ 80,000	$ 292,000
Valuation allowance	0	0
Fair value	$ 80,000	$ 292,000
Foreclosed Assets Held For Sale \| Valuation, Market Approach \| Residential mortgage \| Weighted average
Valuation Techniques and the Unobservable Inputs
Discount rate	36.00%	46.00%

The fair value of foreclosed real estate.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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- Definition

Amount of allowance for credit losses related to recorded investment.

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-Topic 310
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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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-Publisher FASB
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For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

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