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INVESTMENT SECURITIES - Securities with Gross Unrealized Losses (Details) $ in Thousands	Jun. 30, 2021 USD ($) security	Dec. 31, 2020 USD ($) security
Securities Held-to-Maturity, Fair Value
Less than 12 months	$ 11,738	$ 7,879
Fair value	11,738	7,879
Securities Held-to-Maturity, Gross Unrealized Losses
Less than 12 months	(262)	(121)
Gross unrealized losses	(262)	(121)
Securities Available-for-Sale, Fair Value
Less than 12 months	27,152	7,722
Fair value	27,152	7,722
Securities Available-for-Sale, Gross Unrealized Losses
Less than 12 months	(282)	(57)
Gross unrealized losses	(282)	(57)
Total, Fair Value
Less than 12 months	38,890	15,601
Fair value	38,890	15,601
Total, Gross Unrealized Losses
Less than 12 months	(544)	(178)
Gross unrealized losses	$ (544)	$ (178)
Number of securities in unrealized loss position | security	26	8
Mortgage-backed
Securities Available-for-Sale, Fair Value
Less than 12 months	$ 22,640	$ 4,010
Fair value	22,640	4,010
Securities Available-for-Sale, Gross Unrealized Losses
Less than 12 months	(185)	(7)
Gross unrealized losses	(185)	(7)
U.S. Government and agency obligations
Securities Held-to-Maturity, Fair Value
Less than 12 months	11,738	7,879
Fair value	11,738	7,879
Securities Held-to-Maturity, Gross Unrealized Losses
Less than 12 months	(262)	(121)
Gross unrealized losses	(262)	(121)
Securities Available-for-Sale, Fair Value
Less than 12 months	1,929	1,961
Fair value	1,929	1,961
Securities Available-for-Sale, Gross Unrealized Losses
Less than 12 months	(71)	(39)
Gross unrealized losses	(71)	(39)
Municipal obligations
Securities Available-for-Sale, Fair Value
Less than 12 months	2,583	1,751
Fair value	2,583	1,751
Securities Available-for-Sale, Gross Unrealized Losses
Less than 12 months	(26)	(11)
Gross unrealized losses	$ (26)	$ (11)

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