INVESTMENT SECURITIES - Amortized cost and fair value of securities available-for-sale (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 39,546	$ 59,100
Gross Unrealized Gains	1,181	212
Gross Unrealized Losses	(73)	(409)
Fair Value	40,654	58,903
U.S. Treasury debt
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	250	250
Gross Unrealized Gains	6	4
Fair Value	256	254
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,000
Gross Unrealized Gains	48
Fair Value	2,048
Association ("GNMA") mortgage-backed securities - residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	28,844	45,490
Gross Unrealized Gains	944	157
Gross Unrealized Losses		(335)
Fair Value	29,788	45,312
Federal National Mortgage Association ("FNMA") mortgage-backed securities - residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,626	2,935
Gross Unrealized Gains	90	11
Gross Unrealized Losses		(29)
Fair Value	2,716	2,917
Corporate collateralized mortgage obligations ("CMO") and mortgage-backed securities ("MBS")
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,826	10,425
Gross Unrealized Gains	93	40
Gross Unrealized Losses	(73)	(45)
Fair Value	5,846	10,420
Small Business Investment Company
Debt Securities, Available-for-sale [Line Items]
Payments to Acquire Investments	500	$ 400
Contractual Obligation	900
Other Assets [Member] \| Small Business Investment Company
Debt Securities, Available-for-sale [Line Items]
Balance with SBIC included in other assets	$ 2,100

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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