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v3.19.3

Securities - Amortized Cost and Fair Value (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2019 USD ($) item | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) item | Sep. 30, 2018 USD ($) | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost | $ 474,856 | $ 474,856 | $ 474,856 | $ 474,856 |  | $ 546,867
Gross Unrealized Gains | 15,115 |  | 15,115 |  |  | 3,229
Gross Unrealized Losses | (1,549) |  | (1,549) |  |  | (8,848)
Fair Value | 488,422 | 488,422 | 488,422 | 488,422 |  | 541,248
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, at Acquisition, at Fair Value | 9,135 | 10,887 | 9,135 | 10,887 |  |
Other disclosures |  |  |  |  |  |
Purchases |  |  | 136,096 | 71,488 |  |
Sales | $ 57,228 | $ 1,917 | $ 177,824 | $ 94,663 |  |
Number of originators | item | 2 |  | 2 |  |  |
Securities pledged to secure deposits and for other purposes | $ 328,800 |  | $ 328,800 |  |  | 311,200
US Treasury Securities [Member] |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost |  |  |  |  | $ 4,009 | 4,006
Gross Unrealized Gains |  |  |  |  | 29 |
Gross Unrealized Losses |  |  |  |  |  | (83)
Fair Value |  |  |  |  | 4,038 | 3,923
US Government Corporations and Agencies Securities [Member] |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost |  |  |  |  | 9,304 | 11,112
Gross Unrealized Losses |  |  |  |  | (161) | (161)
Fair Value |  |  |  |  | 9,143 | 10,951
U.S. government agencies mortgage-backed |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost |  |  |  |  |  | 14,407
Gross Unrealized Gains |  |  |  |  |  | 45
Gross Unrealized Losses |  |  |  |  |  | (377)
Fair Value |  |  |  |  |  | 14,075
US States and Political Subdivisions Debt Securities [Member] |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost | 227,680 |  | 227,680 |  |  | 277,112
Gross Unrealized Gains | 11,962 |  | 11,962 |  |  | 1,916
Gross Unrealized Losses | (915) |  | (915) |  |  | (4,961)
Fair Value | 238,727 |  | 238,727 |  |  | 274,067
Collateralized Mortgage Obligations [Member] |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost | 62,965 |  | 62,965 |  |  | 66,494
Gross Unrealized Gains | 1,216 |  | 1,216 |  |  | 79
Gross Unrealized Losses | (60) |  | (60) |  |  | (2,144)
Fair Value | 64,121 |  | 64,121 |  |  | 64,429
Asset-backed Securities [Member] |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost | 82,106 |  | 82,106 |  |  | 108,574
Gross Unrealized Gains | 1,243 |  | 1,243 |  |  | 1,165
Gross Unrealized Losses | (167) |  | (167) |  |  | (225)
Fair Value | 83,182 |  | 83,182 |  |  | 109,514
FFEL |  |  |  |  |  |
Other disclosures |  |  |  |  |  |
Asset-backed securities | 55,700 |  | $ 55,700 |  |  |
Percentage of outstanding principal amount of loans guaranteed by US Department of Education |  |  | 97.00 |  |  |
Total added credit enhancement in the form of overcollaterization and/or subordination of outstanding principal | 4,700 |  | $ 4,700 |  |  |
Percentage of total added credit enhancement in the form of overcollaterization and/or subordination of outstanding principal |  |  | 8.30 |  |  |
FFEL | Reimbursement requests greater than 5 % |  |  |  |  |  |
Other disclosures |  |  |  |  |  |
Percentage of outstanding principal amount of loans guaranteed by US Department of Education |  |  | 85.00 |  |  |
Percent of insured loan |  |  | 5.00 |  |  |
FFEL | Reimbursement requests greater than 9 % |  |  |  |  |  |
Other disclosures |  |  |  |  |  |
Percentage of outstanding principal amount of loans guaranteed by US Department of Education |  |  | 75.00 |  |  |
Percent of insured loan |  |  | 9.00 |  |  |
Collateralized loan obligations |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost | 72,454 |  | $ 72,454 |  |  | 65,162
Gross Unrealized Gains | 46 |  | 46 |  |  | 24
Gross Unrealized Losses | (229) |  | (229) |  |  | (897)
Fair Value | 72,271 |  | 72,271 |  |  | $ 64,289
Mortgage Backed Securities, Issued by US Government Agencies [Member] |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost |  |  |  |  | 16,338 |
Gross Unrealized Gains |  |  |  |  | 619 |
Gross Unrealized Losses |  |  |  |  | (17) |
Fair Value |  |  |  |  | $ 16,940 |
GCO Education Loan Funding Corp [Member] |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost | 27,840 |  | 27,840 |  |  |
Fair Value | 27,744 |  | 27,744 |  |  |
Towd Point Mortgage Trust |  |  |  |  |  |
Securities Available-for-Sale |  |  |  |  |  |
Amortized Cost | 33,744 |  | 33,744 |  |  |
Fair Value | $ 34,378 |  | $ 34,378 |  |  |
Towd Point Mortgage Trust | Stockholders' Equity, Total [Member] |  |  |  |  |  |
Other disclosures |  |  |  |  |  |
Credit risk as a percentage of benchmark |  |  | 10.00% |  |  |
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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