INVESTMENT SECURITIES - Summary of investment securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Amortized cost, as adjusted	$ 78,241	$ 71,778
Gross unrealized holding gains	2
Gross unrealized holding losses	951	1,482
Estimated fair value	77,292	70,296
Short-term Investments [Member] \| Obligations of domestic governmental agencies [Member]
Amortized cost, as adjusted	78,241	59,374
Gross unrealized holding gains	2
Gross unrealized holding losses	951	1,053
Estimated fair value	$ 77,292	58,321
Long-term investments [Member] \| Obligations of domestic governmental agencies [Member]
Amortized cost, as adjusted		12,404
Gross unrealized holding losses		429
Estimated fair value		$ 11,975

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

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