INVESTMENT SECURITIES - Investments gross unrealized losses and fair value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
U.S. government agencies - GSEs [Member]
Securities available for sale:
Less Than 12 Months Fair value	$ 872	$ 1,224
Less Than 12 Months Unrealized losses	0	(6)
12 Months or More Fair value	621	4,086
12 Months or More Unrealized losses	(2)	(45)
Total Fair value	1,493	5,310
Total Unrealized losses	(2)	(51)
Mortgage-backed securities - GSEs [Member]
Securities available for sale:
Less Than 12 Months Fair value	2,672	200
Less Than 12 Months Unrealized losses	(3)	0
12 Months or More Fair value	3,774	16,932
12 Months or More Unrealized losses	(10)	(229)
Total Fair value	6,446	17,132
Total Unrealized losses	(13)	(229)
Corporate bonds [Member]
Securities available for sale:
Less Than 12 Months Fair value	0
Less Than 12 Months Unrealized losses	0	0
12 Months or More Fair value	0	0
12 Months or More Unrealized losses	0	0
Total Fair value	0
Total Unrealized losses	0	0
Municipal bonds [Member]
Securities available for sale:
Less Than 12 Months Fair value	0	1,007
Less Than 12 Months Unrealized losses	0	(2)
12 Months or More Fair value	0	1,740
12 Months or More Unrealized losses	0	(22)
Total Fair value	0	2,747
Total Unrealized losses	0	(24)
Total temporarily impaired securities [Member]
Securities available for sale:
Less Than 12 Months Fair value	3,544	2,431
Less Than 12 Months Unrealized losses	(3)	(8)
12 Months or More Fair value	4,395	22,758
12 Months or More Unrealized losses	(12)	(296)
Total Fair value	7,939	25,189
Total Unrealized losses	$ (15)	$ (304)