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FAIR VALUE DISCLOSURES - Financial assets and financial liabilities measured at fair value on a recurring basis (Details) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Financial Assets
Securities available for sale		$ 235,438,000	$ 231,262,000
Financial Liabilities
Transfers from level 1 and level 2		0	0
Transfers from level 2 and level 1		0	0
Transfers from level 1 and level 2		0	0
Transfers from level 2 and level 1		0	0
Transfers into level 3		0	0
Transfers from level 3	$ 0		0
Recurring basis
Financial Assets
Total financial assets		245,549,000	233,900,000
Financial Liabilities
Total financial liabilities		10,178,000	2,638,000
Level 1 Inputs \| Recurring basis \| Equity securities
Financial Assets
Securities available for sale		1,187,000	1,147,000
Level 2 Inputs \| Recurring basis
Financial Liabilities
Credit risk participation agreement		67,000
Level 2 Inputs \| Recurring basis \| Interest rate swaps with customers
Financial Assets
Interest rate swaps assets		10,111,000	2,638,000
Level 2 Inputs \| Recurring basis \| Interest rate swaps
Financial Liabilities
Interest rate swaps liabilities		10,111,000	2,638,000
Level 2 Inputs \| Recurring basis \| State and municipal securities
Financial Assets
Securities available for sale		64,906,000	53,279,000
Level 2 Inputs \| Recurring basis \| Collateralized mortgage obligations
Financial Assets
Securities available for sale		44,100,000	55,989,000
Level 2 Inputs \| Recurring basis \| Mortgage-backed securities
Financial Assets
Securities available for sale		$ 125,245,000	$ 120,847,000