SECURITIES - Securities carrying amount (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($) security	Dec. 31, 2019 USD ($) security	Jun. 30, 2019 USD ($)
SECURITIES.
Securities sold during the year	$ 0
Carrying amount of securities sold in the period			$ 358,000
Carrying value of securities pledged	$ 35,500,000	$ 50,800,000
Securities held in a gross unrealized loss position | security	5	27
Impairment loss on securities	$ 0
Accrued interest receivable for securities	$ 1.0	$ 1,100,000