INVESTMENT SECURITIES - Amortized cost and fair value of AFS investments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale:
Amortized cost	$ 71,199	$ 51,609
Gross unrealized gains	1,183	228
Gross unrealized losses	(15)	(304)
Fair value	72,367	51,533
U.S. government agencies - GSEs [Member]
Securities available for sale:
Amortized cost	9,839	9,852
Gross unrealized gains	159	36
Gross unrealized losses	(2)	(51)
Fair value	9,996	9,837
Mortgage-backed securities - GSEs [Member]
Securities available for sale:
Amortized cost	46,926	23,150
Gross unrealized gains	830	62
Gross unrealized losses	(13)	(229)
Fair value	47,743	22,983
Corporate bonds [Member]
Securities available for sale:
Amortized cost	2,282	1,697
Gross unrealized gains	17	25
Gross unrealized losses	0	0
Fair value	2,299	1,722
Municipal bonds [Member]
Securities available for sale:
Amortized cost	12,152	16,910
Gross unrealized gains	177	105
Gross unrealized losses	0	(24)
Fair value	$ 12,329	$ 16,991

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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