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Investment Securities (Tables) | 9 Months Ended
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Sep. 30, 2024
Investment Securities |
Summary of amortized cost and fair value of securities available-for-sale | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | September 30, 2024
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
(Dollars in thousands) | ​ | Cost |  | Gains |  | (Losses) |  | Value
Available-for-sale | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |
U.S. Treasuries | ​ | $ | 30,892 | ​ | $ | — | ​ | $ | (888) | ​ | $ | 30,004
U.S. government and federal agencies | ​ |  | 13,939 | ​ |  | — | ​ |  | (318) | ​ |  | 13,621
Corporate bonds | ​ |  | 3,000 | ​ |  | — | ​ |  | (345) | ​ |  | 2,655
U.S. agency collateralized mortgage obligations | ​ |  | 38,508 | ​ |  | — | ​ |  | (5,602) | ​ |  | 32,906
Tax-exempt municipal | ​ |  | 1,379 | ​ |  | — | ​ |  | (158) | ​ |  | 1,221
Taxable municipal | ​ |  | 270 | ​ |  | — | ​ |  | (9) | ​ |  | 261
U.S. agency mortgage-backed | ​ |  | 68,438 | ​ |  | — | ​ |  | (4,457) | ​ |  | 63,981
Total Available-for-sale Securities | ​ | $ | 156,426 | ​ | $ | — | ​ | $ | (11,777) | ​ | $ | 144,649
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | December 31, 2023
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
(Dollars in thousands) | ​ | Cost |  | Gains |  | (Losses) |  | Value
Available-for-sale | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |
U.S. Treasuries | ​ | $ | 44,793 | ​ | $ | — | ​ | $ | (1,816) | ​ | $ | 42,977
U.S. government and federal agencies | ​ |  | 13,850 | ​ |  | — | ​ |  | (575) | ​ |  | 13,275
Corporate bonds | ​ |  | 3,000 | ​ |  | — | ​ |  | (477) | ​ |  | 2,523
U.S. agency collateralized mortgage obligations | ​ |  | 40,806 | ​ |  | — | ​ |  | (6,496) | ​ |  | 34,310
Tax-exempt municipal | ​ |  | 1,380 | ​ |  | — | ​ |  | (149) | ​ |  | 1,231
Taxable municipal | ​ |  | 606 | ​ |  | — | ​ |  | (19) | ​ |  | 587
U.S. agency mortgage-backed | ​ |  | 81,255 | ​ |  | — | ​ |  | (6,165) | ​ |  | 75,090
Total Available-for-sale Securities | ​ | $ | 185,690 | ​ | $ | — | ​ | $ | (15,697) | ​ | $ | 169,993
Schedule of gross unrealized loss position of investments | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | September 30, 2024
​ | ​ | Less than 12 Months | ​ | 12 Months or Longer | ​ | Total
​ | ​ | ​ | ​ | Gross | ​ | ​ | ​ | Gross | ​ | ​ | ​ | ​ | Gross
​ | ​ | Fair |  | Unrealized |  | Fair |  | Unrealized |  | Fair |  | Unrealized
(Dollars in thousands) | ​ | Value | ​ | Losses | ​ | Value | ​ | Losses | ​ | Value | ​ | Losses
Available-for-sale | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |
U.S. Treasuries | ​ | $ | — | ​ | $ | — | ​ | $ | 30,004 | ​ | $ | (888) | ​ | $ | 30,004 | ​ | $ | (888)
U.S. government and federal agencies | ​ |  | — | ​ |  | — | ​ |  | 13,621 | ​ |  | (318) | ​ |  | 13,621 | ​ |  | (318)
Corporate bonds | ​ |  | — | ​ |  | — | ​ |  | 2,655 | ​ |  | (345) | ​ |  | 2,655 | ​ |  | (345)
U.S. agency collateralized mortgage obligations | ​ |  | — | ​ |  | — | ​ |  | 32,906 | ​ |  | (5,602) | ​ |  | 32,906 | ​ |  | (5,602)
Tax-exempt municipal | ​ |  | — | ​ |  | — | ​ |  | 1,221 | ​ |  | (158) | ​ |  | 1,221 | ​ |  | (158)
Taxable municipal | ​ |  | — | ​ |  | — | ​ |  | 261 | ​ |  | (9) | ​ |  | 261 | ​ |  | (9)
U.S. agency mortgage-backed | ​ |  | — | ​ |  | — | ​ |  | 63,981 | ​ |  | (4,457) | ​ |  | 63,981 | ​ |  | (4,457)
Total Available-for-sale Securities | ​ | $ | — | ​ | $ | — | ​ | $ | 144,649 | ​ | $ | (11,777) | ​ | $ | 144,649 | ​ | $ | (11,777)
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | December 31, 2023
​ | ​ | Less than 12 Months | ​ | 12 Months or Longer | ​ | Total
​ | ​ | ​ | ​ | Gross | ​ | ​ | ​ | Gross | ​ | ​ | ​ | ​ | Gross
​ | ​ | Fair | ​ | Unrealized | ​ | Fair | ​ | Unrealized | ​ | Fair | ​ | Unrealized
(Dollars in thousands) | ​ | Value |  | Losses |  | Value |  | Losses |  | Value |  | Losses
Available-for-sale | ​ |  | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasuries | ​ | $ | — | ​ | $ | — | ​ | $ | 42,977 | ​ | $ | (1,816) | ​ | $ | 42,977 | ​ | $ | (1,816)
U.S. government and federal agencies | ​ |  | — | ​ |  | — | ​ |  | 13,275 | ​ |  | (575) | ​ |  | 13,275 | ​ |  | (575)
Corporate bonds | ​ | ​ | — | ​ |  | — | ​ |  | 2,523 | ​ |  | (477) | ​ |  | 2,523 | ​ |  | (477)
U.S. agency collateralized mortgage obligations | ​ |  | — | ​ |  | — | ​ |  | 34,310 | ​ |  | (6,496) | ​ |  | 34,310 | ​ |  | (6,496)
Tax-exempt municipal | ​ | ​ | — | ​ |  | — | ​ |  | 1,231 | ​ |  | (149) | ​ |  | 1,231 | ​ |  | (149)
Taxable municipal | ​ |  | — | ​ |  | — | ​ |  | 587 | ​ |  | (19) | ​ |  | 587 | ​ |  | (19)
U.S. agency mortgage-backed | ​ |  | — | ​ |  | — | ​ |  | 75,090 | ​ |  | (6,165) | ​ |  | 75,090 | ​ |  | (6,165)
Total Available-for-sale Securities | ​ | $ | — | ​ | $ | — | ​ | $ | 169,993 | ​ | $ | (15,697) | ​ | $ | 169,993 | ​ | $ | (15,697)
Contractual maturities of investment securities | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | September 30, 2024
​ | ​ | Amortized | ​ | Fair
(Dollars in thousands) |  | Cost |  | Value
Available-for-sale | ​ |  |  | ​ |  |
Due in one year or less | ​ | $ | 23,710 | ​ | $ | 23,463
Due after one year through five years | ​ |  | 35,095 | ​ |  | 33,934
Due after five years through ten years | ​ |  | 40,145 | ​ |  | 38,487
Due after ten years | ​ |  | 57,476 | ​ |  | 48,765
Total Available-for-sale Securities | ​ | $ | 156,426 | ​ | $ | 144,649
​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | September 30, 2024
​ | ​ | Amortized | ​ | Fair
(Dollars in thousands) |  | Cost |  | Value
Held-to-maturity |  | ​ |  |  | ​ |
Due in one year or less | ​ | $ | — | ​ | $ | —
Due after one year through five years | ​ |  | 25,428 | ​ |  | 23,212
Due after five years through ten years | ​ |  | 23,647 | ​ |  | 20,555
Due after ten years | ​ |  | 43,788 | ​ |  | 35,964
Total Held-to-maturity Securities | ​ | $ | 92,863 | ​ | $ | 79,731
Summary of amortized cost and fair value of securities held-to-maturity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | September 30, 2024
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
(Dollars in thousands) | ​ | Cost |  | Gains |  | (Losses) |  | Value
Held-to-maturity |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |
U.S. Treasuries | ​ | $ | 6,002 | ​ | $ | — | ​ | $ | (501) | ​ | $ | 5,501
U.S. government and federal agencies | ​ |  | 35,359 | ​ |  | — | ​ |  | (3,874) | ​ |  | 31,485
U.S. agency collateralized mortgage obligations | ​ |  | 18,227 | ​ |  | — | ​ |  | (3,511) | ​ |  | 14,716
Taxable municipal | ​ |  | 6,045 | ​ |  | — | ​ |  | (887) | ​ |  | 5,158
U.S. agency mortgage-backed | ​ |  | 27,230 | ​ |  | — | ​ |  | (4,359) | ​ |  | 22,871
Total Held-to-maturity Securities | ​ | $ | 92,863 | ​ | $ | — | ​ | $ | (13,132) | ​ | $ | 79,731
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | December 31, 2023
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
(Dollars in thousands) | ​ | Cost |  | Gains |  | (Losses) |  | Value
Held-to-maturity |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |
U.S. Treasuries | ​ | $ | 6,001 | ​ | $ | — | ​ | $ | (667) | ​ | $ | 5,334
U.S. government and federal agencies | ​ |  | 35,434 | ​ |  | — | ​ |  | (5,100) | ​ |  | 30,334
U.S agency collateralized mortgage obligations | ​ |  | 19,395 | ​ |  | — | ​ |  | (4,095) | ​ |  | 15,300
Taxable municipal | ​ |  | 6,057 | ​ |  | — | ​ |  | (1,101) | ​ |  | 4,956
U.S. agency mortgage-backed | ​ |  | 28,618 | ​ |  | — | ​ |  | (5,010) | ​ |  | 23,608
Total Held-to-maturity Securities | ​ | $ | 95,505 | ​ | $ | — | ​ | $ | (15,973) | ​ | $ | 79,532
Summary of restricted securities | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
(Dollars in thousands) |  | September 30, 2024 |  | December 31, 2023
Federal Reserve Bank Stock | ​ | $ | 3,323 | ​ | $ | 3,310
Federal Home Loan Bank Stock | ​ |  | 4,247 | ​ |  | 1,642
Community Bankers’ Bank Stock | ​ |  | 60 | ​ |  | 60
Total Restricted Securities | ​ | $ | 7,630 | ​ | $ | 5,012

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