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v3.19.1

Securities - Amortized Cost and Fair Value (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 USD ($) item | Mar. 31, 2018 USD ($) | Dec. 31, 2018 USD ($)
Securities Available-for-Sale |  |  |
Amortized Cost | $ 505,544 | $ 505,544 | $ 546,867
Gross Unrealized Gains | 8,077 |  | 3,229
Gross Unrealized Losses | (4,531) |  | (8,848)
Fair Value | 509,090 | 509,090 | 541,248
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, at Acquisition, at Fair Value | 10,851 |  |
Other disclosures |  |  |
Purchases | 46,176 | 23,930 |
Sales | $ 81,524 | $ 2,522 |
Number of originators | item | 3 |  |
Securities pledged to secure deposits and for other purposes | $ 321,800 |  | 318,400
US Treasury Securities [Member] |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | 4,007 |  | 4,006
Gross Unrealized Losses | (47) |  | (83)
Fair Value | 3,960 |  | 3,923
US Government Corporations and Agencies Securities [Member] |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | 10,511 |  | 11,112
Gross Unrealized Losses | (151) |  | (161)
Fair Value | 10,360 |  | 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 | 276,463 |  | 277,112
Gross Unrealized Gains | 6,796 |  | 1,916
Gross Unrealized Losses | (2,087) |  | (4,961)
Fair Value | 281,172 |  | 274,067
Collateralized Mortgage Obligations [Member] |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | 65,354 |  | 66,494
Gross Unrealized Gains | 182 |  | 79
Gross Unrealized Losses | (1,206) |  | (2,144)
Fair Value | 64,330 |  | 64,429
Asset-backed Securities [Member] |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | 70,123 |  | 108,574
Gross Unrealized Gains | 838 |  | 1,165
Gross Unrealized Losses | (150) |  | (225)
Fair Value | 70,811 |  | 109,514
FFEL |  |  |
Other disclosures |  |  |
Asset-backed securities | $ 55,600 |  |
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 | $ 11,700 |  |
Percentage of total added credit enhancement in the form of overcollaterization and/or subordination of outstanding principal | 12.44 |  |
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 | $ 63,808 |  | 65,162
Gross Unrealized Gains | 79 |  | 24
Gross Unrealized Losses | (736) |  | (897)
Fair Value | 63,151 |  | $ 64,289
Mortgage Backed Securities, Issued by US Government Agencies [Member] |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | 15,278 |  |
Gross Unrealized Gains | 182 |  |
Gross Unrealized Losses | (154) |  |
Fair Value | 15,306 |  |
GCO Education Loan Funding Corp [Member] |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | 27,777 |  |
Fair Value | 27,731 |  |
Towd Point Mortgage Trust |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | 34,118 |  |
Fair Value | $ 33,679 |  |
Towd Point Mortgage Trust | Stockholders' Equity, Total [Member] |  |  |
Other disclosures |  |  |
Credit risk as a percentage of benchmark | 10.00% |  |
Student Marketing Association [Member] |  |  |
Securities Available-for-Sale |  |  |
Amortized Cost | $ 25,824 |  |
Fair Value | $ 26,153 |  |
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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