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Investment Securities (Tables) | 9 Months Ended
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Sep. 30, 2024
Investments [Abstract] |
Amortized Cost and Fair Value of Investment Securities | The amortized cost and fair value of investment securities are summarized below (in thousands):
|  | Amortized |  |  | Unrealized |  |  | Unrealized |  |  | Fair |
|  | Cost |  |  | Gains |  |  | Losses |  |  | Value |
September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |
Securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agency and government sponsored enterprises |  | $ | 24,535 |  |  | $ | — |  |  | $ | 1,947 |  |  | $ | 22,588 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 421,611 |  |  |  | 4 |  |  |  | 49,964 |  |  |  | 371,651 |
Federal Home Loan Mortgage Corporation |  |  | 374,630 |  |  |  | 549 |  |  |  | 50,573 |  |  |  | 324,606 |
Government National Mortgage Association |  |  | 120,796 |  |  |  | 221 |  |  |  | 19,415 |  |  |  | 101,602 |
Collateralized mortgage obligations: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 10,131 |  |  |  | — |  |  |  | 1,927 |  |  |  | 8,204 |
Federal Home Loan Mortgage Corporation |  |  | 37,123 |  |  |  | 562 |  |  |  | 3,607 |  |  |  | 34,078 |
Government National Mortgage Association |  |  | 14,367 |  |  |  | 631 |  |  |  | — |  |  |  | 14,998 |
Privately issued |  |  | — |  |  |  | 382 |  |  |  | — |  |  |  | 382 |
Total mortgage-backed securities |  |  | 978,658 |  |  |  | 2,349 |  |  |  | 125,486 |  |  |  | 855,521 |
Other debt securities |  |  | 8,656 |  |  |  | 51 |  |  |  | — |  |  |  | 8,707 |
Total available for sale securities |  | $ | 1,011,849 |  |  | $ | 2,400 |  |  | $ | 127,433 |  |  | $ | 886,816 |
Securities held to maturity: |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agency and government sponsored enterprises |  | $ | 16,626 |  |  | $ | — |  |  | $ | 213 |  |  | $ | 16,413 |
State and political subdivisions |  |  | 48,472 |  |  |  | 17 |  |  |  | 4,284 |  |  |  | 44,205 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 5,284 |  |  |  | — |  |  |  | 379 |  |  |  | 4,905 |
Federal Home Loan Mortgage Corporation |  |  | 7,407 |  |  |  | — |  |  |  | 1,086 |  |  |  | 6,321 |
Government National Mortgage Association |  |  | 18,810 |  |  |  | — |  |  |  | 1,440 |  |  |  | 17,370 |
Collateralized mortgage obligations: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 9,556 |  |  |  | — |  |  |  | 538 |  |  |  | 9,018 |
Federal Home Loan Mortgage Corporation |  |  | 11,971 |  |  |  | — |  |  |  | 561 |  |  |  | 11,410 |
Government National Mortgage Association |  |  | 3,156 |  |  |  | — |  |  |  | 185 |  |  |  | 2,971 |
Total mortgage-backed securities |  |  | 56,184 |  |  |  | — |  |  |  | 4,189 |  |  |  | 51,995 |
Total held to maturity securities |  |  | 121,282 |  |  | $ | 17 |  |  | $ | 8,686 |  |  | $ | 112,613 |
Allowance for credit losses – securities |  |  | (3 | ) |  |  |  |  |  |  |  |  |
Total held to maturity securities, net |  | $ | 121,279 |  |  |  |  |  |  |  |  |  |
December 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |
Securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agencies and government sponsored enterprises |  | $ | 24,535 |  |  | $ | — |  |  | $ | 2,724 |  |  | $ | 21,811 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 449,418 |  |  |  | — |  |  |  | 61,219 |  |  |  | 388,199 |
Federal Home Loan Mortgage Corporation |  |  | 402,399 |  |  |  | 488 |  |  |  | 59,665 |  |  |  | 343,222 |
Government National Mortgage Association |  |  | 126,417 |  |  |  | 252 |  |  |  | 21,409 |  |  |  | 105,260 |
Collateralized mortgage obligations: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 10,954 |  |  |  | — |  |  |  | 2,343 |  |  |  | 8,611 |
Federal Home Loan Mortgage Corporation |  |  | 19,766 |  |  |  | — |  |  |  | 4,186 |  |  |  | 15,580 |
Government National Mortgage Association |  |  | 4,501 |  |  |  | 221 |  |  |  | — |  |  |  | 4,722 |
Privately issued |  |  | — |  |  |  | 325 |  |  |  | — |  |  |  | 325 |
Total mortgage-backed securities |  |  | 1,013,455 |  |  |  | 1,286 |  |  |  | 148,822 |  |  |  | 865,919 |
Total available for sale securities |  | $ | 1,037,990 |  |  | $ | 1,286 |  |  | $ | 151,546 |  |  | $ | 887,730 |
(3.) INVESTMENT SECURITIES (Continued)
|  | Amortized |  |  | Unrealized |  |  | Unrealized |  |  | Fair |
|  | Cost |  |  | Gains |  |  | Losses |  |  | Value |
December 31, 2023 (continued) |  |  |  |  |  |  |  |  |  |  |  |
Securities held to maturity: |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agencies and government sponsored enterprises |  | $ | 16,513 |  |  | $ | — |  |  | $ | 530 |  |  | $ | 15,983 |
State and political subdivisions |  |  | 68,854 |  |  |  | 34 |  |  |  | 5,106 |  |  |  | 63,782 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 5,729 |  |  |  | — |  |  |  | 467 |  |  |  | 5,262 |
Federal Home Loan Mortgage Corporation |  |  | 7,648 |  |  |  | — |  |  |  | 1,269 |  |  |  | 6,379 |
Government National Mortgage Association |  |  | 20,223 |  |  |  | — |  |  |  | 1,703 |  |  |  | 18,520 |
Collateralized mortgage obligations: |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 11,432 |  |  |  | — |  |  |  | 851 |  |  |  | 10,581 |
Federal Home Loan Mortgage Corporation |  |  | 14,196 |  |  |  | — |  |  |  | 968 |  |  |  | 13,228 |
Government National Mortgage Association |  |  | 3,565 |  |  |  | — |  |  |  | 270 |  |  |  | 3,295 |
Total mortgage-backed securities |  |  | 62,793 |  |  |  | — |  |  |  | 5,528 |  |  |  | 57,265 |
Total held to maturity securities |  |  | 148,160 |  |  | $ | 34 |  |  | $ | 11,164 |  |  | $ | 137,030 |
Allowance for credit losses – securities |  |  | (4 | ) |  |  |  |  |  |  |  |  |
Total held to maturity securities, net |  | $ | 148,156 |  |  |  |  |  |  |  |  |  |
Scheduled Maturities of Securities Available for Sale and Securities Held to Maturity | The scheduled maturities of securities available for sale and securities held to maturity at September 30, 2024 are shown below (in thousands). Actual expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations.
|  | Amortized |  |  | Fair |
|  | Cost |  |  | Value |
Debt securities available for sale: |  |  |  |  |  |
Due in one year or less |  | $ | 16 |  |  | $ | 16 |
Due from one to five years |  |  | 91,628 |  |  |  | 85,664 |
Due after five years through ten years |  |  | 87,217 |  |  |  | 80,109 |
Due after ten years |  |  | 832,988 |  |  |  | 721,027 |
Total available for sale securities |  | $ | 1,011,849 |  |  | $ | 886,816 |
Debt securities held to maturity: |  |  |  |  |  |
Due in one year or less |  | $ | 18,896 |  |  | $ | 18,771 |
Due from one to five years |  |  | 21,975 |  |  |  | 21,257 |
Due after five years through ten years |  |  | 22,940 |  |  |  | 21,487 |
Due after ten years |  |  | 57,471 |  |  |  | 51,098 |
Total held to maturity securities |  | $ | 121,282 |  |  | $ | 112,613 |
Investments Gross Unrealized Losses and Fair Value | Unrealized losses on investment securities for which an allowance for credit losses has not been recorded and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows (in thousands):
|  | Less than 12 months |  |  | 12 months or longer |  |  | Total |
|  | Fair |  |  | Unrealized |  |  | Fair |  |  | Unrealized |  |  | Fair |  |  | Unrealized |
|  | Value |  |  | Losses |  |  | Value |  |  | Losses |  |  | Value |  |  | Losses |
September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agencies and government sponsored enterprises |  | $ | — |  |  | $ | — |  |  | $ | 22,588 |  |  | $ | 1,947 |  |  | $ | 22,588 |  |  | $ | 1,947 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | — |  |  |  | — |  |  |  | 371,447 |  |  |  | 49,964 |  |  |  | 371,447 |  |  |  | 49,964 |
Federal Home Loan Mortgage Corporation |  |  | — |  |  |  | — |  |  |  | 301,234 |  |  |  | 50,573 |  |  |  | 301,234 |  |  |  | 50,573 |
Government National Mortgage Association |  |  | 15 |  |  |  | — |  |  |  | 86,117 |  |  |  | 19,415 |  |  |  | 86,132 |  |  |  | 19,415 |
Collateralized mortgage obligations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | — |  |  |  | — |  |  |  | 8,204 |  |  |  | 1,927 |  |  |  | 8,204 |  |  |  | 1,927 |
Federal Home Loan Mortgage Corporation |  |  | — |  |  |  | — |  |  |  | 15,010 |  |  |  | 3,607 |  |  |  | 15,010 |  |  |  | 3,607 |
Total mortgage-backed securities |  |  | 15 |  |  |  | — |  |  |  | 782,012 |  |  |  | 125,486 |  |  |  | 782,027 |  |  |  | 125,486 |
Total available for sale securities |  |  | 15 |  |  |  | — |  |  |  | 804,600 |  |  |  | 127,433 |  |  |  | 804,615 |  |  |  | 127,433 |
Other debt securities |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Total AFS debt securities with unrealized losses |  | $ | 15 |  |  | $ | — |  |  | $ | 804,600 |  |  | $ | 127,433 |  |  | $ | 804,615 |  |  | $ | 127,433 |
December 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Government agencies and government sponsored enterprises |  | $ | — |  |  | $ | — |  |  | $ | 21,811 |  |  | $ | 2,724 |  |  | $ | 21,811 |  |  | $ | 2,724 |
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | 8 |  |  |  | — |  |  |  | 388,191 |  |  |  | 61,219 |  |  |  | 388,199 |  |  |  | 61,219 |
Federal Home Loan Mortgage Corporation |  |  | — |  |  |  | — |  |  |  | 314,854 |  |  |  | 59,665 |  |  |  | 314,854 |  |  |  | 59,665 |
Government National Mortgage Association |  |  | — |  |  |  | — |  |  |  | 86,475 |  |  |  | 21,409 |  |  |  | 86,475 |  |  |  | 21,409 |
Collateralized mortgage obligations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal National Mortgage Association |  |  | — |  |  |  | — |  |  |  | 8,611 |  |  |  | 2,343 |  |  |  | 8,611 |  |  |  | 2,343 |
Federal Home Loan Mortgage Corporation |  |  | — |  |  |  | — |  |  |  | 15,580 |  |  |  | 4,186 |  |  |  | 15,580 |  |  |  | 4,186 |
Total mortgage-backed securities |  |  | 8 |  |  |  | — |  |  |  | 813,711 |  |  |  | 148,822 |  |  |  | 813,719 |  |  |  | 148,822 |
Total available for sale securities |  |  | 8 |  |  |  | — |  |  |  | 835,522 |  |  |  | 151,546 |  |  |  | 835,530 |  |  |  | 151,546 |
Total AFS debt securities with unrealized losses |  | $ | 8 |  |  | $ | — |  |  | $ | 835,522 |  |  | $ | 151,546 |  |  | $ | 835,530 |  |  | $ | 151,546 |

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