INVESTMENT SECURITIES - Amortized cost and fair value of securities held-to-maturity (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Investment securities held-to-maturity:
Amortized Cost	$ 79,636,000	$ 81,056,000
Gross Unrecognized Gains	12,000	13,000
Gross Unrecognized Losses	(6,078,000)	(6,351,000)
Fair Value	73,570,000	74,718,000
Allowance for credit losses: held-to-maturity securities	(71,000)	0
U.S. Treasury debt
Investment securities held-to-maturity:
Amortized Cost	245,000	243,000
Gross Unrecognized Gains	0	0
Gross Unrecognized Losses	(7,000)	(9,000)
Fair Value	238,000	234,000
Allowance for credit losses: held-to-maturity securities	0
Corporate bonds
Investment securities held-to-maturity:
Amortized Cost	23,780,000	23,819,000
Gross Unrecognized Gains	0	0
Gross Unrecognized Losses	(2,674,000)	(2,453,000)
Fair Value	21,106,000	21,366,000
Allowance for credit losses: held-to-maturity securities	(71,000)	0
GNMA mortgage-backed securities – residential
Investment securities held-to-maturity:
Amortized Cost	38,465,000	39,426,000
Gross Unrecognized Gains	0	0
Gross Unrecognized Losses	(2,480,000)	(2,800,000)
Fair Value	35,985,000	36,626,000
Allowance for credit losses: held-to-maturity securities	0
FNMA mortgage-backed securities – residential
Investment securities held-to-maturity:
Amortized Cost	6,554,000	6,708,000
Gross Unrecognized Gains	0	0
Gross Unrecognized Losses	(427,000)	(506,000)
Fair Value	6,127,000	6,202,000
Allowance for credit losses: held-to-maturity securities	0
Government CMO and MBS - commercial
Investment securities held-to-maturity:
Amortized Cost	6,540,000	6,786,000
Gross Unrecognized Gains	12,000	13,000
Gross Unrecognized Losses	(324,000)	(403,000)
Fair Value	6,228,000	6,396,000
Allowance for credit losses: held-to-maturity securities	0
Corporate CMO and MBS
Investment securities held-to-maturity:
Amortized Cost	4,052,000	4,074,000
Gross Unrecognized Gains	0	0
Gross Unrecognized Losses	(166,000)	(180,000)
Fair Value	3,886,000	3,894,000
Allowance for credit losses: held-to-maturity securities	$ 0	$ 0

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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