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v3.21.1

Borrowings - Additional Information (Details) - USD ($) |  |  | 1 Months Ended | 3 Months Ended |
--- | --- | --- | --- | --- | ---
Feb. 17, 2021 | Feb. 09, 2021 | Mar. 31, 2020 | Mar. 31, 2021 | Dec. 31, 2020
Line of Credit Facility [Line Items] |  |  |  |  |
Short-term borrowings |  |  |  | $ 0 | $ 0
Vertical risk retention interest |  | 5.00% | 5.00% | 5.00% |
Unsecured offering issued |  |  |  |  | 1,343,000,000
Uncommitted federal funds |  |  |  | $ 125,000,000 |
Lendable value of collateral |  |  |  | 3,200,000,000 | 3,800,000,000
Student Loan |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Private education loans sold |  | $ 2,500,000,000 |  |  |
Additional net proceeds from sales of loans held for investment, capitalized interest |  | 130,000,000 |  |  |
Gain on sale |  | $ 18,000,000 |  |  |
Unsecured borrowings |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Short-term borrowings |  |  |  | 0 | 0
Commercial Paper | ABCP borrowings |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Private asset backed commercial paper education loan funding facility | $ 2,000,000,000 |  |  |  |
Ownership interest percentage in residual interest in ABCP facility | 100.00% |  |  |  |
Short-term borrowings |  |  |  | $ 0 | $ 0

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