LOANS AND ALLOWANCE FOR LOAN LOSSES (Narrative) (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($) contract	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Unpaid principal balance of loans	$ 23,840,000		$ 23,849,000
Accretable discount on the acquired covered loans	597,000	$ 816,000
Total loans	2,212,210,000		2,185,635,000
Accretable discount on loans	$ 10,600,000		11,200,000
TDRs during period | contract	0
TDR, subsequent default, number of contracts | contract	0
Mortgage loans on real estate, foreclosures	$ 1,200,000		1,400,000
Mortgage loans in process of foreclosure, amount	2,000.0		1,900,000
SBA guaranteed amounts included in nonaccrual loans	2,900,000		4,100,000
Doubtful [Member]
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 0		$ 0