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Securities (Tables) | 12 Months Ended
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Dec. 31, 2023
Securities |
Schedule of amortized cost and fair value of the securities portfolio and corresponding amounts of gross unrealized gains and losses recognized in accumulated other comprehensive loss | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
December 31, 2023 |  | Cost1 |  | Gains |  | Losses | ​ | Value
Securities available-for-sale | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury | ​ | $ | 174,602 | ​ | $ | - | ​ | $ | (5,028) | ​ | $ | 169,574
U.S. government agencies | ​ | ​ | 60,011 | ​ | ​ | - | ​ | ​ | (3,052) | ​ | ​ | 56,959
U.S. government agencies mortgage-backed | ​ | ​ | 118,492 | ​ | ​ | - | ​ | ​ | (12,122) | ​ | ​ | 106,370
States and political subdivisions | ​ | ​ | 238,440 | ​ | ​ | 1,325 | ​ | ​ | (10,430) | ​ | ​ | 229,335
Collateralized mortgage obligations | ​ | ​ | 442,987 | ​ | ​ | 421 | ​ | ​ | (50,864) | ​ | ​ | 392,544
Asset-backed securities | ​ | ​ | 69,248 | ​ | ​ | 42 | ​ | ​ | (3,124) | ​ | ​ | 66,166
Collateralized loan obligations | ​ | ​ | 173,201 | ​ | ​ | 30 | ​ | ​ | (1,350) | ​ | ​ | 171,881
Total securities available-for-sale | ​ | $ | 1,276,981 | ​ | $ | 1,818 | ​ | $ | (85,970) | ​ | $ | 1,192,829
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
December 31, 2022 |  | Cost1 |  | Gains |  | Losses | ​ | Value
Securities available-for-sale | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury | ​ | $ | 224,054 | ​ | $ | - | ​ | $ | (11,925) | ​ | $ | 212,129
U.S. government agencies | ​ | ​ | 61,178 | ​ | ​ | - | ​ | ​ | (5,130) | ​ | ​ | 56,048
U.S. government agencies mortgage-backed | ​ | ​ | 140,588 | ​ | ​ | - | ​ | ​ | (15,598) | ​ | ​ | 124,990
States and political subdivisions | ​ | ​ | 239,999 | ​ | ​ | 363 | ​ | ​ | (14,234) | ​ | ​ | 226,128
Corporate bonds | ​ | ​ | 10,000 | ​ | ​ | - | ​ | ​ | (378) | ​ | ​ | 9,622
Collateralized mortgage obligations | ​ | ​ | 596,336 | ​ | ​ | 1 | ​ | ​ | (62,569) | ​ | ​ | 533,768
Asset-backed securities | ​ | ​ | 210,388 | ​ | ​ | 6 | ​ | ​ | (8,466) | ​ | ​ | 201,928
Collateralized loan obligations | ​ | ​ | 180,276 | ​ | ​ | - | ​ | ​ | (5,530) | ​ | ​ | 174,746
Total securities available-for-sale | ​ | $ | 1,662,819 | ​ | $ | 370 | ​ | $ | (123,830) | ​ | $ | 1,539,359
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
1 Excludes interest receivable of $6.6 million and $6.8 million at December 31, 2023 and December 31, 2022, respectively, that is recorded in other assets on the consolidated balance sheets.
Schedule of fair value, amortized cost and weighted average yield of debt securities by contractual maturity along with securities not due at a single maturity date, primarily mortgage-backed securities (MBS), asset-backed securities, and collateralized loan obligations | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Weighted | ​ | ​ | ​ | ​ | ​
​ | ​ | Amortized | ​ | Average | ​ | ​ | Fair | ​
Securities available-for-sale |  | Cost |  | Yield | ​ |  | Value |
Due in one year or less | ​ | $ | 150,067 | ​ | 1.06 | % | ​ | $ | 146,728 | ​
Due after one year through five years | ​ | ​ | 99,527 | ​ | 1.36 | ​ | ​ | ​ | 94,572 | ​
Due after five years through ten years | ​ | ​ | 59,571 | ​ | 2.92 | ​ | ​ | ​ | 55,005 | ​
Due after ten years | ​ | ​ | 163,888 | ​ | 3.11 | ​ | ​ | ​ | 159,563 | ​
​ | ​ | ​ | 473,053 | ​ | 2.07 | ​ | ​ | ​ | 455,868 | ​
Mortgage-backed and collateralized mortgage obligations | ​ | ​ | 561,479 | ​ | 2.42 | ​ | ​ | ​ | 498,914 | ​
Asset-backed securities | ​ | ​ | 69,248 | ​ | 4.35 | ​ | ​ | ​ | 66,166 | ​
Collateralized loan obligations | ​ | ​ | 173,201 | ​ | 7.14 | ​ | ​ | ​ | 171,881 | ​
Total securities available-for-sale | ​ | $ | 1,276,981 | ​ | 3.03 | % | ​ | $ | 1,192,829 | ​
Schedule of securities with unrealized losses aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position | Securities with unrealized losses with no corresponding allowance for credit losses at December 31, 2023 and 2022 aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows (in thousands except for number of securities): ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Less than 12 months | ​ | 12 months or more | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
December 31, 2023 | ​ | in an unrealized loss position | ​ | in an unrealized loss position | ​ | Total
​ | ​ | Number of | ​ | Unrealized | ​ | Fair | ​ | Number of | ​ | Unrealized | ​ | Fair | ​ | Number of | ​ | Unrealized | ​ | Fair
Securities available-for-sale |  | Securities |  | Losses |  | Value |  | Securities |  | Losses |  | Value |  | Securities |  | Losses |  | Value
U.S. Treasuries | ​ | - | ​ | $ | - | ​ | $ | - | ​ | 4 | ​ | $ | 5,028 | ​ | $ | 169,574 | ​ | 4 | ​ | $ | 5,028 | ​ | $ | 169,574
U.S. government agencies | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 9 | ​ | ​ | 3,052 | ​ | ​ | 56,959 | ​ | 9 | ​ | ​ | 3,052 | ​ | ​ | 56,959
U.S. government agencies mortgage-backed | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 128 | ​ | ​ | 12,122 | ​ | ​ | 106,370 | ​ | 128 | ​ | ​ | 12,122 | ​ | ​ | 106,370
States and political subdivisions | ​ | 12 | ​ | ​ | 137 | ​ | ​ | 27,974 | ​ | 27 | ​ | ​ | 10,293 | ​ | ​ | 108,408 | ​ | 39 | ​ | ​ | 10,430 | ​ | ​ | 136,382
Collateralized mortgage obligations | ​ | 2 | ​ | ​ | 8 | ​ | ​ | 734 | ​ | 143 | ​ | ​ | 50,856 | ​ | ​ | 376,236 | ​ | 145 | ​ | ​ | 50,864 | ​ | ​ | 376,970
Asset-backed securities | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 17 | ​ | ​ | 3,124 | ​ | ​ | 61,671 | ​ | 17 | ​ | ​ | 3,124 | ​ | ​ | 61,671
Collateralized loan obligations | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 25 | ​ | ​ | 1,350 | ​ | ​ | 150,902 | ​ | 25 | ​ | ​ | 1,350 | ​ | ​ | 150,902
Total securities available-for-sale | ​ | 14 | ​ | $ | 145 | ​ | $ | 28,708 | ​ | 353 | ​ | $ | 85,825 | ​ | $ | 1,030,120 | ​ | 367 | ​ | $ | 85,970 | ​ | $ | 1,058,828
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Less than 12 months | ​ | 12 months or more | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
December 31, 2022 | ​ | in an unrealized loss position | ​ | in an unrealized loss position | ​ | Total
​ | ​ | Number of | ​ | Unrealized | ​ | ​ | Fair | ​ | Number of | ​ | Unrealized | ​ | ​ | Fair | ​ | Number of | ​ | Unrealized | ​ | ​ | Fair
Securities available-for-sale |  | Securities |  | Losses |  | ​ | Value |  | Securities |  | Losses |  | ​ | Value |  | Securities |  | Losses |  | ​ | Value
U.S. Treasuries | ​ | 1 | ​ | $ | 1,025 | ​ | $ | 24,121 | ​ | 4 | ​ | $ | 10,900 | ​ | $ | 188,008 | ​ | 5 | ​ | $ | 11,925 | ​ | $ | 212,129
U.S. government agencies | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 9 | ​ | ​ | 5,130 | ​ | ​ | 56,048 | ​ | 9 | ​ | ​ | 5,130 | ​ | ​ | 56,048
U.S. government agencies mortgage-backed | ​ | 15 | ​ | ​ | 975 | ​ | ​ | 11,369 | ​ | 117 | ​ | ​ | 14,623 | ​ | ​ | 113,621 | ​ | 132 | ​ | ​ | 15,598 | ​ | ​ | 124,990
States and political subdivisions | ​ | 45 | ​ | ​ | 5,800 | ​ | ​ | 128,770 | ​ | 15 | ​ | ​ | 8,434 | ​ | ​ | 48,877 | ​ | 60 | ​ | ​ | 14,234 | ​ | ​ | 177,647
Corporate bonds | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 2 | ​ | ​ | 378 | ​ | ​ | 9,622 | ​ | 2 | ​ | ​ | 378 | ​ | ​ | 9,622
Collateralized mortgage obligations | ​ | 80 | ​ | ​ | 12,895 | ​ | ​ | 180,624 | ​ | 120 | ​ | ​ | 49,674 | ​ | ​ | 348,880 | ​ | 200 | ​ | ​ | 62,569 | ​ | ​ | 529,504
Asset-backed securities | ​ | 30 | ​ | ​ | 3,030 | ​ | ​ | 121,915 | ​ | 21 | ​ | ​ | 5,436 | ​ | ​ | 79,659 | ​ | 51 | ​ | ​ | 8,466 | ​ | ​ | 201,574
Collateralized loan obligations | ​ | 23 | ​ | ​ | 3,579 | ​ | ​ | 112,772 | ​ | 11 | ​ | ​ | 1,951 | ​ | ​ | 61,974 | ​ | 34 | ​ | ​ | 5,530 | ​ | ​ | 174,746
Total securities available-for-sale | ​ | 194 | ​ | $ | 27,304 | ​ | $ | 579,571 | ​ | 299 | ​ | $ | 96,526 | ​ | $ | 906,689 | ​ | 493 | ​ | $ | 123,830 | ​ | $ | 1,486,260
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Schedule of securities available for sale net realized gains (losses) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Year Ended | ​
​ | ​ | December 31, | ​
Securities available-for-sale |  | 2023 |  | 2022 |  | 2021 | ​
Proceeds from sales of securities | ​ | $ | 205,738 | ​ | $ | 30,981 | ​ | $ | 605,846 | ​
Gross realized gains on securities | ​ |  | - | ​ |  | - | ​ |  | 270 | ​
Gross realized losses on securities | ​ |  | (4,148) | ​ |  | (944) | ​ |  | (38) | ​
Net realized (losses) gains | ​ | $ | (4,148) | ​ | $ | (944) | ​ | $ | 232 | ​
Income tax benefit (expense) on net realized (losses) gains | ​ | $ | 1,117 | ​ | $ | 265 | ​ | $ | (65) | ​
Effective tax rate applied | ​ | ​ | 26.9 | % | ​ | 28.1 | % | ​ | 28.0 | ​
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- Definition For all investments in an unrealized loss position, including those for which other-than-temporary impairments have not been recognized in earnings (including investments for which a portion of an other-than-temporary impairment has been recognized in other comprehensive income), a tabular disclosure of the aggregate related fair value of investments with unrealized losses and the aggregate amount of unrealized losses by categories of investments and length of time (that is, the amount by which amortized cost basis exceeds fair value). + References No definition available. + Details
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