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v3.20.2

Securities - Amortized Cost and Fair Value (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) item | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($)
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | $ 428,439 |  | $ 475,146
Gross Unrealized Gains |  | 23,365 |  | 13,285
Gross Unrealized Losses |  | (3,383) |  | (3,783)
Fair Value |  | 448,421 |  | 484,648
Accrued interest receivable |  | 2,600 |  | 3,200
Other disclosures |  |  |  |
Purchases |  | 14,681 | $ 136,096 |
Sales | $ 57,228 | $ 18,006 | $ 177,824 |
Number of originators | item |  | 1 |  |
Securities pledged to secure deposits and for other purposes |  | $ 353,200 |  | 320,800
US Treasury Securities [Member] |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | 4,013 |  | 4,010
Gross Unrealized Gains |  | 121 |  | 26
Fair Value |  | 4,134 |  | 4,036
US Government Corporations and Agencies Securities [Member] |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | 7,169 |  | 8,502
Gross Unrealized Losses |  | (164) |  | (165)
Fair Value |  | 7,005 |  | 8,337
U.S. government agencies mortgage-backed |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  |  |  | 16,164
Gross Unrealized Gains |  |  |  | 443
Gross Unrealized Losses |  |  |  | (19)
Fair Value |  |  |  | 16,588
US States and Political Subdivisions Debt Securities [Member] |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | 232,416 |  | 240,399
Gross Unrealized Gains |  | 18,316 |  | 11,207
Gross Unrealized Losses |  | (955) |  | (2,431)
Fair Value |  | 249,777 |  | 249,175
Collateralized Mortgage Obligations [Member] |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | 54,597 |  | 57,059
Gross Unrealized Gains |  | 2,839 |  | 963
Gross Unrealized Losses |  | (423) |  | (38)
Fair Value |  | 57,013 |  | 57,984
Asset-backed Securities [Member] |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | 81,986 |  | 82,114
Gross Unrealized Gains |  | 905 |  | 617
Gross Unrealized Losses |  | (1,306) |  | (887)
Fair Value |  | 81,585 |  | 81,844
FFEL |  |  |  |
Other disclosures |  |  |  |
Asset-backed securities |  | $ 55,900 |  |
Percentage of outstanding principal amount of loans guaranteed by US Department of Education |  | 97 |  |
Total added credit enhancement in the form of overcollaterization and/or subordination of outstanding principal |  | $ 5,100 |  |
Percentage of total added credit enhancement in the form of overcollaterization and/or subordination of outstanding principal |  | 9.00 |  |
FFEL | Reimbursement requests greater than 5 % |  |  |  |
Other disclosures |  |  |  |
Percentage of outstanding principal amount of loans guaranteed by US Department of Education |  | 85 |  |
Percent of insured loan |  | 5 |  |
FFEL | Reimbursement requests greater than 9 % |  |  |  |
Other disclosures |  |  |  |
Percentage of outstanding principal amount of loans guaranteed by US Department of Education |  | 75 |  |
Percent of insured loan |  | 9 |  |
Collateralized loan obligations |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | $ 31,202 |  | 66,898
Gross Unrealized Gains |  | 19 |  | 29
Gross Unrealized Losses |  | (533) |  | (243)
Fair Value |  | 30,688 |  | $ 66,684
Mortgage Backed Securities, Issued by US Government Agencies [Member] |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | 17,056 |  |
Gross Unrealized Gains |  | 1,165 |  |
Gross Unrealized Losses |  | (2) |  |
Fair Value |  | 18,219 |  |
Towd Point Mortgage Trust |  |  |  |
Securities Available-for-Sale |  |  |  |
Amortized Cost |  | 33,242 |  |
Fair Value |  | $ 35,477 |  |
Stockholders' Equity, Total [Member] | GCO Education Loan Funding Corp [Member] |  |  |  |
Other disclosures |  |  |  |
Credit risk as a percentage of benchmark |  | 10.00% |  |

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