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Securities (Tables) | 9 Months Ended
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Sep. 30, 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
September 30, 2023 |  | Cost1 |  | Gains |  | Losses | ​ | Value
Securities available-for-sale | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury | ​ | $ | 224,481 | ​ | $ | - | ​ | $ | (7,704) | ​ | $ | 216,777
U.S. government agencies | ​ | ​ | 60,197 | ​ | ​ | - | ​ | ​ | (4,376) | ​ | ​ | 55,821
U.S. government agencies mortgage-backed | ​ | ​ | 122,653 | ​ | ​ | - | ​ | ​ | (18,084) | ​ | ​ | 104,569
States and political subdivisions | ​ | ​ | 240,107 | ​ | ​ | 142 | ​ | ​ | (20,149) | ​ | ​ | 220,100
Corporate bonds | ​ | ​ | 5,000 | ​ | ​ | - | ​ | ​ | (39) | ​ | ​ | 4,961
Collateralized mortgage obligations | ​ | ​ | 450,470 | ​ | ​ | 54 | ​ | ​ | (63,845) | ​ | ​ | 386,679
Asset-backed securities | ​ | ​ | 71,241 | ​ | ​ | - | ​ | ​ | (4,325) | ​ | ​ | 66,916
Collateralized loan obligations | ​ | ​ | 175,995 | ​ | ​ | 10 | ​ | ​ | (2,210) | ​ | ​ | 173,795
Total securities available-for-sale | ​ | $ | 1,350,144 | ​ | $ | 206 | ​ | $ | (120,732) | ​ | $ | 1,229,618
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ ​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | 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 accrued interest receivable of $6.7 million and $6.8 million at September 30, 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 | ​ | $ | 49,989 | ​ | 0.64 | % | ​ | $ | 49,804 | ​
Due after one year through five years | ​ | ​ | 253,955 | ​ | 1.17 | ​ | ​ | ​ | 241,430 | ​
Due after five years through ten years | ​ | ​ | 60,975 | ​ | 2.92 | ​ | ​ | ​ | 53,882 | ​
Due after ten years | ​ | ​ | 164,866 | ​ | 3.11 | ​ | ​ | ​ | 152,543 | ​
​ | ​ | ​ | 529,785 | ​ | 1.92 | ​ | ​ | ​ | 497,659 | ​
Mortgage-backed and collateralized mortgage obligations | ​ | ​ | 573,123 | ​ | 2.29 | ​ | ​ | ​ | 491,248 | ​
Asset-backed securities | ​ | ​ | 71,241 | ​ | 4.24 | ​ | ​ | ​ | 66,916 | ​
Collateralized loan obligations | ​ | ​ | 175,995 | ​ | 7.21 | ​ | ​ | ​ | 173,795 | ​
Total securities available-for-sale | ​ | $ | 1,350,144 | ​ | 3.00 | % | ​ | $ | 1,229,618 | ​
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 | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Less than 12 months | ​ | 12 months or more | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
September 30, 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 | ​ | - | ​ | $ | - | ​ | $ | - | ​ | 5 | ​ | $ | 7,704 | ​ | $ | 216,777 | ​ | 5 | ​ | $ | 7,704 | ​ | $ | 216,777
U.S. government agencies | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 9 | ​ | ​ | 4,376 | ​ | ​ | 55,821 | ​ | 9 | ​ | ​ | 4,376 | ​ | ​ | 55,821
U.S. government agencies mortgage-backed | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 128 | ​ | ​ | 18,084 | ​ | ​ | 104,569 | ​ | 128 | ​ | ​ | 18,084 | ​ | ​ | 104,569
States and political subdivisions | ​ | 44 | ​ | ​ | 3,232 | ​ | ​ | 110,511 | ​ | 30 | ​ | ​ | 16,917 | ​ | ​ | 104,582 | ​ | 74 | ​ | ​ | 20,149 | ​ | ​ | 215,093
Corporate bonds | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 1 | ​ | ​ | 39 | ​ | ​ | 4,961 | ​ | 1 | ​ | ​ | 39 | ​ | ​ | 4,961
Collateralized mortgage obligations | ​ | 2 | ​ | ​ | 14 | ​ | ​ | 756 | ​ | 146 | ​ | ​ | 63,831 | ​ | ​ | 379,159 | ​ | 148 | ​ | ​ | 63,845 | ​ | ​ | 379,915
Asset-backed securities | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 19 | ​ | ​ | 4,325 | ​ | ​ | 66,916 | ​ | 19 | ​ | ​ | 4,325 | ​ | ​ | 66,916
Collateralized loan obligations | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 33 | ​ | ​ | 2,210 | ​ | ​ | 170,803 | ​ | 33 | ​ | ​ | 2,210 | ​ | ​ | 170,803
Total securities available-for-sale | ​ | 46 | ​ | $ | 3,246 | ​ | $ | 111,267 | ​ | 371 | ​ | $ | 117,486 | ​ | $ | 1,103,588 | ​ | 417 | ​ | $ | 120,732 | ​ | $ | 1,214,855
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | 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 proceeds from sale and gross realized gains and losses on sale of securities | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | Three Months Ended | ​ | ​ | Nine Months Ended | ​ | ​
​ | ​ | ​ | September 30, | ​ | ​ | September 30, | ​ | ​
Securities available-for-sale |  | 2023 |  | 2022 |  | 2023 |  | 2022 |  | ​
Proceeds from sales of securities | ​ | $ | 65,572 | ​ | $ | - | ​ | $ | 205,738 | ​ | $ | 3,303 | ​ | ​
Gross realized losses on securities | ​ |  | (924) | ​ |  | (1) | ​ |  | (4,146) | ​ |  | (34) | ​ | ​
Net realized losses | ​ | $ | (924) | ​ | $ | (1) | ​ | $ | (4,146) | ​ | $ | (34) | ​ | ​
Income tax benefit on net realized losses | ​ | $ | 260 | ​ | $ | 1 | ​ | $ | 1,165 | ​ | $ | 10 | ​ | ​
Effective tax rate applied | ​ | ​ | 28.1 | % | ​ | N/M | ​ | ​ | 28.1 | % | ​ | 29.4 | % | ​

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