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INVESTMENT SECURITIES - Equity and Other Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Equity and Other Securities [Abstract] |  |
Amortized cost | $ 43,955 | $ 46,511
Gross unrealized gains | 968 | 944
Gross unrealized losses | 0 | 0
Equity and other securities (cost of $43,955 and $46,511, respectively) | 44,923 | 47,455
Equity Securities, at Fair Value [Abstract] |  |
Amortized cost | 251 | 251
Gross unrealized gains | 218 | 194
Gross unrealized losses | 0 | 0
Fair value | 469 | 445
Federal Home Loan Bank Common Stock [Member] |  |
Other Equity Securities, at Adjusted Cost [Abstract] |  |
Amortized cost | 7,262 | 7,468
Gross unrealized gains | 0 | 0
Gross unrealized losses | 0 | 0
Fair value | 7,262 | 7,468
Federal Reserve Bank Stock [Member] |  |
Other Equity Securities, at Adjusted Cost [Abstract] |  |
Amortized cost | 33,916 | 33,916
Gross unrealized gains | 0 | 0
Gross unrealized losses | 0 | 0
Fair value | 33,916 | 33,916
Other Equity Securities [Member] |  |
Other Equity Securities, at Adjusted Cost [Abstract] |  |
Amortized cost | 2,526 | 4,876
Gross unrealized gains | 750 | 750
Gross unrealized losses | 0 | 0
Fair value | $ 3,276 | $ 5,626

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