INVESTMENT SECURITIES - Securities with unrealized losses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair Value	$ 4,899	$ 4,369
Less than 12 months, Unrealized Losses	(41)	(51)
12 months or Longer, Fair Value	659	566
12 months or Longer, Unrealized Losses	(24)	(13)
Total Fair Value	5,558	4,935
Total Unrealized Losses	(65)	(64)
Government National Mortgage Association ("GNMA") mortgage-backed securities - residential
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair Value	881
Less than 12 months, Unrealized Losses	(3)
Total Fair Value	881
Total Unrealized Losses	(3)
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair Value	3,962	3,489
Less than 12 months, Unrealized Losses	(38)	(11)
Total Fair Value	3,962	3,489
Total Unrealized Losses	(38)	(11)
Corporate collateralized mortgage obligations ("CMO") and MBS
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, Fair Value	56	880
Less than 12 months, Unrealized Losses		(40)
12 months or Longer, Fair Value	659	566
12 months or Longer, Unrealized Losses	(24)	(13)
Total Fair Value	715	1,446
Total Unrealized Losses	$ (24)	$ (53)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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