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INVESTMENT SECURITIES (Tables) | 12 Months Ended
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Dec. 31, 2023
INVESTMENT SECURITIES |
Schedule of amortized cost and fair value of securities available-for-sale and securities held-to-maturity | The following tables summarizes the amortized cost and fair value of AFS and HTM debt securities and equity investments and the corresponding amounts of gross unrealized gains and losses recognized in accumulated other comprehensive income (loss) and gross unrecognized gains and losses recognized in earnings (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Unrealized/ | ​ | Unrealized/ | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrecognized | ​ | Unrecognized | ​ | ​ | ​
At December 31, 2023 |  | Cost |  | Gains |  | Losses |  | Fair Value
Available-for-Sale Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Government agency securities | ​ | $ | 67,997 | ​ | $ | — | ​ | $ | (6,222) | ​ | $ | 61,775
U.S. State and Municipal securities | ​ | ​ | 11,496 | ​ | ​ | — | ​ | ​ | (1,797) | ​ | ​ | 9,699
Residential MBS | ​ | ​ | 419,331 | ​ | ​ | 1,198 | ​ | ​ | (68,609) | ​ | ​ | 351,920
Commercial MBS | ​ | ​ | 36,879 | ​ | ​ | 71 | ​ | ​ | (2,366) | ​ | ​ | 34,584
Asset-backed securities | ​ | ​ | 3,287 | ​ | ​ | — | ​ | ​ | (58) | ​ | ​ | 3,229
Total securities available-for-sale | ​ | $ | 538,990 | ​ | $ | 1,269 | ​ | $ | (79,052) | ​ | $ | 461,207
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Held-to-Maturity Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury securities | ​ | $ | 29,895 | ​ | $ | — | ​ | $ | (1,412) | ​ | $ | 28,483
U.S. State and Municipal securities | ​ | ​ | 15,569 | ​ | ​ | — | ​ | ​ | (1,574) | ​ | ​ | 13,995
Residential MBS | ​ | ​ | 415,306 | ​ | ​ | — | ​ | ​ | (60,556) | ​ | ​ | 354,750
Commercial MBS | ​ | ​ | 8,090 | ​ | ​ | — | ​ | ​ | (1,066) | ​ | ​ | 7,024
Total securities held-to-maturity | ​ | $ | 468,860 | ​ | $ | — | ​ | $ | (64,608) | ​ | $ | 404,252
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Equity Investments: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
CRA Mutual Fund | ​ | $ | 2,410 | ​ | $ | — | ​ | $ | (287) | ​ | $ | 2,123
Total equity investment securities | ​ | $ | 2,410 | ​ | $ | — | ​ | $ | (287) | ​ | $ | 2,123
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Unrealized/ | ​ | Unrealized/ | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrecognized | ​ | Unrecognized | ​ | ​ | ​
At December 31, 2022 |  | Cost |  | Gains |  | Losses |  | Fair Value
Available-for-Sale Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Government agency securities | ​ | $ | 67,996 | ​ | $ | — | ​ | $ | (8,624) | ​ | $ | 59,372
U.S. State and Municipal securities | ​ | ​ | 11,649 | ​ | ​ | — | ​ | ​ | (2,437) | ​ | ​ | 9,212
Residential MBS | ​ | ​ | 413,998 | ​ | ​ | 279 | ​ | ​ | (75,729) | ​ | ​ | 338,548
Commercial MBS | ​ | ​ | 37,069 | ​ | ​ | 10 | ​ | ​ | (2,229) | ​ | ​ | 34,850
Asset-backed securities | ​ | ​ | 3,953 | ​ | ​ | — | ​ | ​ | (188) | ​ | ​ | 3,765
Total securities available-for-sale | ​ | $ | 534,665 | ​ | $ | 289 | ​ | $ | (89,207) | ​ | $ | 445,747
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Held-to-Maturity Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury securities | ​ | $ | 29,852 | ​ | $ | — | ​ | $ | (2,223) | ​ | $ | 27,629
U.S. State and Municipal securities | ​ | ​ | 15,814 | ​ | ​ | — | ​ | ​ | (2,609) | ​ | ​ | 13,205
Residential MBS | ​ | ​ | 456,648 | ​ | ​ | — | ​ | ​ | (67,027) | ​ | ​ | 389,621
Commercial MBS | ​ | ​ | 8,111 | ​ | ​ | — | ​ | ​ | (1,276) | ​ | ​ | 6,835
Total securities held-to-maturity | ​ | $ | 510,425 | ​ | $ | — | ​ | $ | (73,135) | ​ | $ | 437,290
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Equity Investments: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
CRA Mutual Fund | ​ | $ | 2,358 | ​ | $ | — | ​ | $ | (310) | ​ | $ | 2,048
Total equity investment securities | ​ | $ | 2,358 | ​ | $ | — | ​ | $ | (310) | ​ | $ | 2,048
Schedule of proceeds from sales and calls of securities and associated gains | The following table summarizes the proceeds and associated gains and (losses) from sales and calls of securities (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Year ended December 31,
​ |  | 2023 |  | 2022 | ​ | 2021
Proceeds | ​ | $ | — | ​ | $ | — | ​ | $ | 43,241
Gross gains | ​ | $ | — | ​ | $ | — | ​ | $ | 609
Tax impact | ​ | $ | — | ​ | $ | — | ​ | $ | (197)
Schedule of amortized cost and fair value of debt securities classified by contractual maturity | The tables below summarize, by contractual maturity, the amortized cost and fair value of debt securities. The tables do not include the effect of principal repayments or scheduled principal amortization. Equity securities, primarily investment in mutual funds, have been excluded from the table. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations with or without call or prepayment penalties (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Held-to-Maturity | ​ | Available-for-Sale
At December 31, 2023 |  | Amortized Cost |  | Fair Value |  | Amortized Cost |  | Fair Value
Due within 1 year | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | —
After 1 year through 5 years | ​ | ​ | 37,984 | ​ | ​ | 35,507 | ​ | ​ | 65,822 | ​ | ​ | 60,757
After 5 years through 10 years | ​ | ​ | 1,112 | ​ | ​ | 1,044 | ​ | ​ | 22,163 | ​ | ​ | 21,174
After 10 years | ​ | ​ | 429,764 | ​ | ​ | 367,701 | ​ | ​ | 451,005 | ​ | ​ | 379,276
Total Securities | ​ | $ | 468,860 | ​ | $ | 404,252 | ​ | $ | 538,990 | ​ | $ | 461,207
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Held-to-Maturity | ​ | Available-for-Sale
At December 31, 2022 |  | Amortized Cost |  | Fair Value |  | Amortized Cost |  | Fair Value
Due within 1 year | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | —
After 1 year through 5 years | ​ | ​ | 29,852 | ​ | ​ | 27,630 | ​ | ​ | 54,736 | ​ | ​ | 48,959
After 5 years through 10 years | ​ | ​ | 9,505 | ​ | ​ | 8,130 | ​ | ​ | 36,043 | ​ | ​ | 32,872
After 10 years | ​ | ​ | 471,068 | ​ | ​ | 401,530 | ​ | ​ | 443,886 | ​ | ​ | 363,916
Total Securities | ​ | $ | 510,425 | ​ | $ | 437,290 | ​ | $ | 534,665 | ​ | $ | 445,747
Schedule of securities with unrealized/unrecognized losses | At December 31, 2023, debt securities with unrealized/unrecognized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, are as follows (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Less than 12 Months | ​ | 12 Months or More | ​ | Total
​ | ​ | ​ | ​ | ​ | Unrealized/ | ​ | ​ | ​ | ​ | Unrealized/ | ​ | ​ | ​ | ​ | Unrealized/
​ | ​ | Estimated | ​ | Unrecognized | ​ | Estimated | ​ | Unrecognized | ​ | Estimated | ​ | Unrecognized
At December 31, 2023 |  | Fair Value |  | Losses |  | Fair Value |  | Losses |  | Fair Value |  | Losses
Available-for-Sale Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Government agency securities | ​ | $ | — | ​ | $ | — | ​ | $ | 61,775 | ​ | $ | (6,222) | ​ | $ | 61,775 | ​ | $ | (6,222)
U.S. State and Municipal securities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 9,699 | ​ | ​ | (1,797) | ​ | ​ | 9,699 | ​ | ​ | (1,797)
Residential MBS | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 292,970 | ​ | ​ | (68,609) | ​ | ​ | 292,970 | ​ | ​ | (68,609)
Commercial MBS | ​ | ​ | 10,873 | ​ | ​ | (198) | ​ | ​ | 13,322 | ​ | ​ | (2,168) | ​ | ​ | 24,195 | ​ | ​ | (2,366)
Asset-backed securities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 3,229 | ​ | ​ | (58) | ​ | ​ | 3,229 | ​ | ​ | (58)
Total securities available-for-sale | ​ | $ | 10,873 | ​ | $ | (198) | ​ | $ | 380,995 | ​ | $ | (78,854) | ​ | $ | 391,868 | ​ | $ | (79,052)
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Held-to-Maturity Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury securities | ​ | $ | — | ​ | $ | — | ​ | $ | 28,483 | ​ | $ | (1,412) | ​ | $ | 28,483 | ​ | $ | (1,412)
U.S. State and Municipal securities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 13,995 | ​ | ​ | (1,574) | ​ | ​ | 13,995 | ​ | ​ | (1,574)
Residential MBS | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 354,750 | ​ | ​ | (60,556) | ​ | ​ | 354,750 | ​ | ​ | (60,556)
Commercial MBS | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 7,024 | ​ | ​ | (1,066) | ​ | ​ | 7,024 | ​ | ​ | (1,066)
Total securities held-to-maturity | ​ | $ | — | ​ | $ | — | ​ | $ | 404,252 | ​ | $ | (64,608) | ​ | $ | 404,252 | ​ | $ | (64,608)
At December 31, 2022, debt securities with unrealized/unrecognized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, are as follows (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Less than 12 Months | ​ | 12 Months or More | ​ | Total
​ | ​ | ​ | ​ | ​ | Unrealized/ | ​ | ​ | ​ | ​ | Unrealized/ | ​ | ​ | ​ | ​ | Unrealized/
​ | ​ | Estimated | ​ | Unrecognized | ​ | Estimated | ​ | Unrecognized | ​ | Estimated | ​ | Unrecognized
At December 31, 2022 |  | Fair Value |  | Losses |  | Fair Value |  | Losses |  | Fair Value |  | Losses
Available-for-Sale Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Government agency securities | ​ | $ | — | ​ | $ | — | ​ | $ | 59,372 | ​ | $ | (8,624) | ​ | $ | 59,372 | ​ | $ | (8,624)
U.S. State and Municipal securities | ​ | ​ | 2,546 | ​ | ​ | (527) | ​ | ​ | 6,666 | ​ | ​ | (1,910) | ​ | ​ | 9,212 | ​ | ​ | (2,437)
Residential MBS | ​ | ​ | 19,576 | ​ | ​ | (1,654) | ​ | ​ | 305,936 | ​ | ​ | (74,075) | ​ | ​ | 325,512 | ​ | ​ | (75,729)
Commercial MBS | ​ | ​ | 13,406 | ​ | ​ | (198) | ​ | ​ | 11,386 | ​ | ​ | (2,031) | ​ | ​ | 24,792 | ​ | ​ | (2,229)
Asset-backed securities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 3,765 | ​ | ​ | (188) | ​ | ​ | 3,765 | ​ | ​ | (188)
Total securities available-for-sale | ​ | $ | 35,528 | ​ | $ | (2,379) | ​ | $ | 387,125 | ​ | $ | (86,828) | ​ | $ | 422,653 | ​ | $ | (89,207)
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Held-to-Maturity Securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury securities | ​ | $ | 18,683 | ​ | $ | (1,365) | ​ | $ | 8,946 | ​ | $ | (858) | ​ | $ | 27,629 | ​ | $ | (2,223)
U.S. State and Municipal securities | ​ | ​ | 13,205 | ​ | ​ | (2,609) | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 13,205 | ​ | ​ | (2,609)
Residential MBS | ​ | ​ | 162,960 | ​ | ​ | (19,625) | ​ | ​ | 226,661 | ​ | ​ | (47,402) | ​ | ​ | 389,621 | ​ | ​ | (67,027)
Commercial MBS | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 6,835 | ​ | ​ | (1,276) | ​ | ​ | 6,835 | ​ | ​ | (1,276)
Total securities held-to-maturity | ​ | $ | 194,848 | ​ | $ | (23,599) | ​ | $ | 242,442 | ​ | $ | (49,536) | ​ | $ | 437,290 | ​ | $ | (73,135)

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