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INVESTMENT SECURITIES - Equity and Other Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Equity and Other Securities [Abstract] |  |
Amortized cost | $ 46,511 | $ 42,965
Gross unrealized gains | 944 | 950
Gross unrealized losses | 0 | 0
Fair value | 47,455 | 43,915
Equity Securities, at Fair Value [Abstract] |  |
Amortized cost | 251 | 251
Gross unrealized gains | 194 | 200
Gross unrealized losses | 0 | 0
Fair value | 445 | 451
Federal Home Loan Bank Common Stock [Member] |  |
Other Equity Securities, at Adjusted Cost [Abstract] |  |
Amortized cost | 7,468 | 7,246
Gross unrealized gains | 0 | 0
Fair value | 7,468 | 7,246
Federal Reserve Bank Stock [Member] |  |
Other Equity Securities, at Adjusted Cost [Abstract] |  |
Amortized cost | 33,916 | 30,922
Gross unrealized gains | 0 | 0
Fair value | 33,916 | 30,922
Other Equity Securities [Member] |  |
Other Equity Securities, at Adjusted Cost [Abstract] |  |
Amortized cost | 4,876 | 4,546
Gross unrealized gains | 750 | 750
Fair value | $ 5,626 | $ 5,296

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