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v3.19.3.a.u2

Subsequent Events (Details) - USD ($) |  |  |  |  |  |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 12, 2020 | Jun. 12, 2019 | Mar. 13, 2019 | Sep. 19, 2018 | Jun. 20, 2018 | Mar. 21, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Feb. 20, 2020 | Feb. 19, 2020 | Feb. 20, 2019
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Unsecured debt issued |  |  |  |  |  |  | $ 0 | $ 0 | $ 197,000,000 |  |  |
Estimated weighted average life of student loans |  |  |  |  |  |  | 5 years 4 months 24 days | 5 years 5 months |  |  |  |
Class A and B Notes |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Estimated weighted average life of student loans |  | 4 years 4 months 28 days | 4 years 3 months 3 days | 4 years 3 months 25 days | 4 years 4 months 24 days | 4 years 5 months 4 days |  |  |  |  |  |
Class A and B Notes | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 1.01% | 92.00% | 0.77% | 0.76% | 0.78% |  |  |  |  |  |
Commercial Paper | ABCP borrowings |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Private education loan funding |  |  |  |  |  |  |  |  |  |  |  | $ 750,000,000
Subsequent Event | Private Education Loans 2020 Term A |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Private education loan term accounted for as a secured financing | $ 636,000,000 |  |  |  |  |  |  |  |  |  |  |
Loans sold to third parties | $ 636,000,000 |  |  |  |  |  |  |  |  |  |  |
Ownership interest percentage on asset-backed financing | 100.00% |  |  |  |  |  |  |  |  |  |  |
Unsecured debt issued | $ 634,000,000 |  |  |  |  |  |  |  |  |  |  |
Subsequent Event | Class A and B Notes |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Estimated weighted average life of student loans | 4 years 2 months 4 days |  |  |  |  |  |  |  |  |  |  |
Subsequent Event | Class A and B Notes | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate | 0.88% |  |  |  |  |  |  |  |  |  |  |
Subsequent Event | Private Education Loans Sold To Third-Party |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Loans sold to third parties |  |  |  |  |  |  |  |  |  | $ 954,000,000 |  |
Accrued interest included in loans sold |  |  |  |  |  |  |  |  |  | $ 68,000,000 |  |
Subsequent Event | Commercial Paper | ABCP borrowings |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Private education loan funding |  |  |  |  |  |  |  |  |  |  | $ 2,000,000,000 |

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