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SECURITIES (Tables) | 12 Months Ended
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Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract] |
Amortized Cost and Estimated Fair Value of Securities Available for Sale | Amortized cost and estimated fair value of securities available for sale at December 31, 2023 and 2022 are as follows (in thousands):
| December 31, 2023
| Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Allowance for Credit Losses |  | Estimated Fair Value
U.S. treasury notes and bonds | $ | 59,812 |  |  | $ | — |  |  | $ | 4,480 |  |  | $ | — |  |  | $ | 55,332 |
Mortgage-backed securities, residential | 476,240 |  |  | 6 |  |  | 72,422 |  |  | — |  |  | 403,824 |
Collateralized mortgage obligations | — |  |  | — |  |  | — |  |  | — |  |  | — |
Obligations of states and political subdivisions | 39,503 |  |  | — |  |  | 817 |  |  | — |  |  | 38,686 |
Corporate bonds and notes | 25,750 |  |  | — |  |  | 5,081 |  |  | — |  |  | 20,669 |
SBA loan pools | 67,787 |  |  | 75 |  |  | 2,380 |  |  | — |  |  | 65,482 |
Total | $ | 669,092 |  |  | $ | 81 |  |  | $ | 85,180 |  |  | $ | — |  |  | $ | 583,993 |
|  | December 31, 2022
|  | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
U.S. treasury notes and bonds |  | $ | 61,800 |  |  | $ | — |  |  | $ | 6,225 |  |  | $ | 55,574 |
Mortgage-backed securities, residential |  | 518,838 |  |  | — |  |  | 83,707 |  |  | 435,131 |
Collateralized mortgage obligations |  | — |  |  | — |  |  | — |  |  | — |
Obligations of states and political subdivisions |  | 39,828 |  |  | 2 |  |  | 938 |  |  | 38,892 |
Corporate bonds and notes |  | 25,750 |  |  | — |  |  | 3,780 |  |  | 21,970 |
SBA loan pools |  | 82,982 |  |  | 155 |  |  | 2,116 |  |  | 81,022 |
Total |  | $ | 729,198 |  |  | $ | 157 |  |  | $ | 96,766 |  |  | $ | 632,589 |
Amortized Cost and Estimated Fair Value of Debt Securities Available for Sale by Contractual Maturity | Securities not due at a single maturity date are shown separately (in thousands):
|  | December 31, 2023
|  | Amortized Cost |  | Estimated Fair Value
Within one year |  | $ | 5,678 |  |  | $ | 5,594 |
After one, but within five years |  | 101,391 |  |  | 94,363 |
After five, but within ten years |  | 17,526 |  |  | 14,302 |
After ten years |  | 470 |  |  | 428 |
Mortgage-backed securities: residential |  | 476,240 |  |  | 403,824 |
SBA loan pools |  | 67,787 |  |  | 65,482 |
Total |  | $ | 669,092 |  |  | $ | 583,993 |
Amortized Cost and Estimated Fair Value of Securities Held to Maturity | Amortized cost and estimated fair value of securities held to maturity at December 31, 2023 and 2022 are as follows (in thousands):
|  | December 31, 2023
|  | Amortized Cost |  | Unrecognized Gains |  | Unrecognized Losses |  | Estimated Fair Value |  | Allowance for Credit Losses
Obligations of states and political subdivisions |  | $ | 785 |  |  | $ | — |  |  | $ | — |  |  | $ | 785 |  |  | $ | — |
Time deposits with other financial institutions |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
|  | $ | 785 |  |  | $ | — |  |  | $ | — |  |  | $ | 785 |  |  | $ | — |
|  | December 31, 2022
|  | Amortized Cost |  | Unrecognized Gains |  | Unrecognized Losses |  | Estimated Fair Value
Obligations of states and political subdivisions |  | $ | 952 |  |  | $ | — |  |  | $ | — |  |  | $ | 952 |
Time deposits with other financial institutions |  | 1,472 |  |  | — |  |  | 22 |  |  | 1,450 |
|  | $ | 2,424 |  |  | $ | — |  |  | $ | 22 |  |  | $ | 2,402 |
Contractual Maturities of Securities Held to Maturity | The contractual maturity of securities held to maturity was as follows at December 31, 2023 (in thousands):
|  | December 31, 2023
|  | Amortized Cost |  | Fair Value
Within one year |  | $ | — |  |  | $ | — |
After one, but within five years |  | 145 |  |  | 145 |
After five, but within ten years |  | 640 |  |  | 640 |
After ten years |  | — |  |  | — |
Total |  | $ | 785 |  |  | $ | 785 |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value | The following tables summarize the investment securities available for sale with unrealized losses, for which an allowance for credit losses has not been recorded as of December 31, 2023, and an other than temporary impairment (OTTI) has not been recorded as of December 31, 2022 aggregated by major security type and length of time in a continuous unrealized loss position (in thousands):
|  | Less than 12 months |  | 12 months or longer |  | Total
|  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses
2023 |
U.S. treasury notes and bonds |  | $ | — |  |  | $ | — |  |  | $ | 55,332 |  |  | $ | 4,480 |  |  | $ | 55,332 |  |  | $ | 4,480 |
Mortgage-backed securities: residential |  | — |  |  | — |  |  | 402,986 |  |  | 72,422 |  |  | 402,986 |  |  | 72,422 |
Obligations of states and political subdivisions |  | 17,891 |  |  | 241 |  |  | 20,686 |  |  | 576 |  |  | 38,577 |  |  | 817 |
Corporate bonds and notes |  | 7,492 |  |  | 2,508 |  |  | 13,177 |  |  | 2,573 |  |  | 20,669 |  |  | 5,081 |
SBA loan pools |  | 3,914 |  |  | 13 |  |  | 54,468 |  |  | 2,367 |  |  | 58,382 |  |  | 2,380 |
Total temporarily impaired securities |  | $ | 29,297 |  |  | $ | 2,762 |  |  | $ | 546,649 |  |  | $ | 82,418 |  |  | $ | 575,946 |  |  | $ | 85,180 |
|  | Less than 12 months |  | 12 months or longer |  | Total
|  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses
2022 |
U.S. treasury notes and bonds |  | $ | 1,011 |  |  | $ | 30 |  |  | $ | 54,563 |  |  | $ | 6,195 |  |  | $ | 55,574 |  |  | $ | 6,225 |
Mortgage-backed securities, residential |  | 79,891 |  |  | 7,621 |  |  | 355,240 |  |  | 76,086 |  |  | 435,131 |  |  | 83,707 |
Obligations of states and political subdivisions |  | 37,847 |  |  | 938 |  |  | — |  |  | — |  |  | 37,847 |  |  | 938 |
Corporate bonds and notes |  | 4,515 |  |  | 485 |  |  | 7,455 |  |  | 3,295 |  |  | 11,970 |  |  | 3,780 |
SBA loan pools |  | 14,333 |  |  | 925 |  |  | 51,123 |  |  | 1,191 |  |  | 65,456 |  |  | 2,116 |
Total temporarily impaired securities |  | $ | 137,597 |  |  | $ | 9,999 |  |  | $ | 468,381 |  |  | $ | 86,767 |  |  | $ | 605,978 |  |  | $ | 96,766 |

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