SECURITIES (Narrative) (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2021 USD ($) security	Dec. 31, 2020 USD ($) security
Debt and Equity Securities, FV-NI [Line Items]
Asset backed securities pledged to secure certain deposits	$ 46,700,000	$ 48,200,000
Asset backed securities pledged as collateral	0	0
Recognized net gains	$ 600,000	$ 1,400,000
Number of securities sold | security	10	42
Securities available for sale ("AFS"), at fair value	$ 253,348,000	$ 246,105,000
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1,821,000	424,000
Other-than temporary impairment charges	0	0
Amortized cost	251,071,000	240,013,000
Available for Sale Securities Sold
Debt and Equity Securities, FV-NI [Line Items]
Securities available for sale ("AFS"), at fair value	11,900,000	62,500,000
Asset-backed securities issued by GSEs and U.S. Agencies
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1,412,000	327,000
Amortized cost	44,900,000	33,300,000
Student Loan Trust Loans and Others
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	70,000	88,000
Amortized cost	8,000,000.0	12,600,000
Student Loan Trust Loans
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost	$ 39,900,000
Available for sale securities, U.S. government guaranteed	97.00%
Asset Backed Securities Issued By States, Political Subdivisions or Agencies
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	$ 300,000
Amortized cost	$ 18,200,000	$ 0