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Borrowings - Pre-2019 Transactions (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2018
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ABS Transactions |  |
Debt Instrument [Line Items] |  |
Private education loan term accounted for as a secured financing |  | $ 5,800
Private Education Loans |  |
Debt Instrument [Line Items] |  |
Private education loan term accounted for as a secured financing | $ 3,700 |
Principal amount of collateral | 3,500 |
Capitalized interest | $ 159 |

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- Definition This is the principal amount outstanding for loans which are in the process of being securitized as of the date of the statement of financial position (across all types of loans). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Details
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- Details
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Period Type: |