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Securities (Tables) | 9 Months Ended
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Sep. 30, 2020
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, 2020 |  | Cost1 |  | Gains |  | Losses | ​ | Value
Securities available-for-sale | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury | ​ | $ | 4,013 | ​ | $ | 121 | ​ | $ | - | ​ | $ | 4,134
U.S. government agencies | ​ | ​ | 7,169 | ​ | ​ | - | ​ | ​ | (164) | ​ | ​ | 7,005
U.S. government agencies mortgage-backed | ​ | ​ | 17,056 | ​ | ​ | 1,165 | ​ | ​ | (2) | ​ | ​ | 18,219
States and political subdivisions | ​ | ​ | 232,416 | ​ | ​ | 18,316 | ​ | ​ | (955) | ​ | ​ | 249,777
Collateralized mortgage obligations | ​ | ​ | 54,597 | ​ | ​ | 2,839 | ​ | ​ | (423) | ​ | ​ | 57,013
Asset-backed securities | ​ | ​ | 81,986 | ​ | ​ | 905 | ​ | ​ | (1,306) | ​ | ​ | 81,585
Collateralized loan obligations | ​ | ​ | 31,202 | ​ | ​ | 19 | ​ | ​ | (533) | ​ | ​ | 30,688
Total securities available-for-sale | ​ | $ | 428,439 | ​ | $ | 23,365 | ​ | $ | (3,383) | ​ | $ | 448,421
​ ​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Unrealized | ​ | Fair
December 31, 2019 |  | Cost1 |  | Gains |  | Losses | ​ | Value
Securities available-for-sale | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury | ​ | $ | 4,010 | ​ | $ | 26 | ​ | $ | - | ​ | $ | 4,036
U.S. government agencies | ​ | ​ | 8,502 | ​ | ​ | - | ​ | ​ | (165) | ​ | ​ | 8,337
U.S. government agencies mortgage-backed | ​ | ​ | 16,164 | ​ | ​ | 443 | ​ | ​ | (19) | ​ | ​ | 16,588
States and political subdivisions | ​ | ​ | 240,399 | ​ | ​ | 11,207 | ​ | ​ | (2,431) | ​ | ​ | 249,175
Collateralized mortgage obligations | ​ | ​ | 57,059 | ​ | ​ | 963 | ​ | ​ | (38) | ​ | ​ | 57,984
Asset-backed securities | ​ | ​ | 82,114 | ​ | ​ | 617 | ​ | ​ | (887) | ​ | ​ | 81,844
Collateralized loan obligations | ​ | ​ | 66,898 | ​ | ​ | 29 | ​ | ​ | (243) | ​ | ​ | 66,684
Total securities available-for-sale | ​ | $ | 475,146 | ​ | $ | 13,285 | ​ | $ | (3,783) | ​ | $ | 484,648
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
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 | ​ | $ | 413 | ​ | 2.01 | % | ​ | $ | 415 | ​
Due after one year through five years | ​ | ​ | 6,056 | ​ | 2.11 | ​ | ​ | ​ | 6,309 | ​
Due after five years through ten years | ​ | ​ | 28,014 | ​ | 2.31 | ​ | ​ | ​ | 28,993 | ​
Due after ten years | ​ | ​ | 209,115 | ​ | 3.03 | ​ | ​ | ​ | 225,199 | ​
​ | ​ | ​ | 243,598 | ​ | 2.92 | ​ | ​ | ​ | 260,916 | ​
Mortgage-backed and collateralized mortgage obligations | ​ | ​ | 71,653 | ​ | 3.08 | ​ | ​ | ​ | 75,232 | ​
Asset-backed securities | ​ | ​ | 81,986 | ​ | 1.51 | ​ | ​ | ​ | 81,585 | ​
Collateralized loan obligations | ​ | ​ | 31,202 | ​ | 2.12 | ​ | ​ | ​ | 30,688 | ​
Total securities available-for-sale | ​ | $ | 428,439 | ​ | 2.62 | % | ​ | $ | 448,421 | ​
Schedule of amortized cost and fair value of securities that exceed 10% of stockholders equity | At September 30, 2020, the Company had invested in securities issued from one originator that individually amounted to over 10% of the Company’s stockholders’ equity. Information regarding this issuer and the value of the securities issued follows: ​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | September 30, 2020
​ |  | Amortized |  | Fair
Issuer | ​ | Cost | ​ | Value
Towd Point Mortgage Trust | ​ | $ | 33,242 | ​ | $ | 35,477
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, 2020 | ​ | 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. government agencies | ​ | - | ​ | $ | - | ​ | $ | - | ​ | 4 | ​ | $ | 164 | ​ | $ | 7,005 | ​ | 4 | ​ | $ | 164 | ​ | $ | 7,005
U.S. government agencies mortgage-backed | ​ | 1 | ​ | ​ | 2 | ​ | ​ | 260 | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 1 | ​ | ​ | 2 | ​ | ​ | 260
States and political subdivisions | ​ | - | ​ | ​ | - | ​ | ​ | - | ​ | 1 | ​ | ​ | 955 | ​ | ​ | 3,872 | ​ | 1 | ​ | ​ | 955 | ​ | ​ | 3,872
Collateralized mortgage obligations | ​ | 4 | ​ | ​ | 421 | ​ | ​ | 8,027 | ​ | 1 | ​ | ​ | 2 | ​ | ​ | 279 | ​ | 5 | ​ | ​ | 423 | ​ | ​ | 8,306
Asset-backed securities | ​ | 5 | ​ | ​ | 425 | ​ | ​ | 22,603 | ​ | 3 | ​ | ​ | 881 | ​ | ​ | 33,069 | ​ | 8 | ​ | ​ | 1,306 | ​ | ​ | 55,672
Collateralized loan obligations | ​ | 1 | ​ | ​ | 123 | ​ | ​ | 7,376 | ​ | 4 | ​ | ​ | 410 | ​ | ​ | 21,245 | ​ | 5 | ​ | ​ | 533 | ​ | ​ | 28,621
Total securities available-for-sale | ​ | 11 | ​ | $ | 971 | ​ | $ | 38,266 | ​ | 13 | ​ | $ | 2,412 | ​ | $ | 65,470 | ​ | 24 | ​ | $ | 3,383 | ​ | $ | 103,736
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Less than 12 months | ​ | 12 months or more | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
December 31, 2019 | ​ | 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. government agencies | ​ | - | ​ | $ | - | ​ | $ | - | ​ | 4 | ​ | $ | 165 | ​ | $ | 8,337 | ​ | 4 | ​ | $ | 165 | ​ | $ | 8,337
U.S. government agencies mortgage-backed | ​ | 3 | ​ | ​ | 10 | ​ | ​ | 3,018 | ​ | 2 | ​ | ​ | 9 | ​ | ​ | 843 | ​ | 5 | ​ | ​ | 19 | ​ | ​ | 3,861
States and political subdivisions | ​ | 6 | ​ | ​ | 1,665 | ​ | ​ | 41,043 | ​ | 2 | ​ | ​ | 766 | ​ | ​ | 6,593 | ​ | 8 | ​ | ​ | 2,431 | ​ | ​ | 47,636
Collateralized mortgage obligations | ​ | 2 | ​ | ​ | 26 | ​ | ​ | 9,054 | ​ | 2 | ​ | ​ | 12 | ​ | ​ | 1,209 | ​ | 4 | ​ | ​ | 38 | ​ | ​ | 10,263
Asset-backed securities | ​ | 4 | ​ | ​ | 839 | ​ | ​ | 54,540 | ​ | 1 | ​ | ​ | 48 | ​ | ​ | 3,238 | ​ | 5 | ​ | ​ | 887 | ​ | ​ | 57,778
Collateralized loan obligations | ​ | 4 | ​ | ​ | 62 | ​ | ​ | 21,927 | ​ | 4 | ​ | ​ | 181 | ​ | ​ | 25,020 | ​ | 8 | ​ | ​ | 243 | ​ | ​ | 46,947
Total securities available-for-sale | ​ | 19 | ​ | $ | 2,602 | ​ | $ | 129,582 | ​ | 15 | ​ | $ | 1,181 | ​ | $ | 45,240 | ​ | 34 | ​ | $ | 3,783 | ​ | $ | 174,822
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
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 |  | 2020 |  | 2019 |  | 2020 |  | 2019 |
Proceeds from sales of securities | ​ | $ | - | ​ | $ | 57,228 | ​ | $ | 18,006 | ​ | $ | 177,824 | ​
Gross realized gains on securities | ​ | $ | - | ​ | $ | 3,841 | ​ | $ | 17 | ​ | $ | 5,432 | ​
Gross realized losses on securities | ​ |  | (1) | ​ |  | (378) | ​ |  | (42) | ​ |  | (956) | ​
Net realized (losses) gains | ​ | $ | (1) | ​ | $ | 3,463 | ​ | $ | (25) | ​ | $ | 4,476 | ​
Income tax (expense) benefit on net realized gains (losses) | ​ | $ | - | ​ | $ | (973) | ​ | $ | 7 | ​ | $ | (1,257) | ​
Effective tax rate applied | ​ | ​ | 0.0 | % | ​ | 28.1 | % | ​ | 28.0 | % | ​ | 28.1 | %

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- Definition Tabular disclosure of the proceeds from sales of available-for-sale securities and the gross realized gains and gross realized losses that have been included in earnings as a result of those sales. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563 + Details
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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 (that is, the amount by which amortized cost basis exceeds fair value). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27290-111563 + Details
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