LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Summary of unpaid principal balance of loans classified as TDRs (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) loan	Mar. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Recorded Investment	$ 12,270	$ 10,451
Allowance for loan associated with TDR	(833)	(683)
Net recorded investment	$ 11,437	9,768
Additional funds to loans classified as TDRs		200
Cash collateral received		1,500
Number of contracts modified | loan	2
Cash, Securities and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Recorded Investment	$ 2,803	1,493
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Recorded Investment	9,467	8,958
Allowance for loan associated with TDR	(833)	(683)
Accrual Loans | Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Recorded Investment	5,055	4,820
Loans on nonaccrual status | Cash, Securities and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Recorded Investment	2,803	1,493
Loans on nonaccrual status | Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Recorded Investment	$ 4,412	$ 4,138