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SECURITIES - Narrative (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) security | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
OTTI, Sales and Calls, Pledged, Trading and Restricted Securities |  |  |
Number of securities in unrealized loss position | security | 0 |  |
Debt securities available for sale, allowance of credit losses | $ 0 |  |
Allowance for credit losses | $ 0 |  |
Guaranteed portion of student loan backed bonds | student loan backed bonds, which are guaranteed by the U.S. Department of Education for 97% to 100% of principal |  |
Credit support for student loan backed bonds description | the bonds have credit support of 3% to 5% |  |
Proceeds from sales of securities available for sale | $ 152,980 | $ 46,478 | $ 230,372
Gross gains realized on sale of securities available for sale | 4,300 | 200 |
Gross losses realized on sale of securities available for sale | 800 |  | (7,900)
Debt and Equity Securities, Gain (Loss) | 3,525 | 201 | (7,921)
Proceeds from calls of securities | 14,900 | 20,300 | $ 3,300
Fair value of securities pledged to secure public deposits and FHLB and FRB overnight borrowings | 402,800 | 402,200 |
Trading securities | $ 0 | $ 0 |
Threshold for disclosure percentage | 10.00% | 10.00% |
Amount owned in FHLB, ACBB and FRB stock | $ 23,362 | $ 32,879 |
Other Assets |  |  |
OTTI, Sales and Calls, Pledged, Trading and Restricted Securities |  |  |
Accrued interest receivable on securities | $ 1,400 |  |

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