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v3.22.2.2

Commitments and Contingencies - Additional Information (Detail) | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Jan. 31, 2022 USD ($) StateAttorneysGeneral Borrower | Dec. 31, 2021 USD ($) | Mar. 31, 2016 Case | Sep. 30, 2022 USD ($)
Loss Contingencies [Line Items] |  |  |  |
Number of cases filed | Case |  |  | 3 |
Number of State Attorneys General under Agreement | StateAttorneysGeneral | 40 |  |  |
Number of borrowers involved in cancellation of loan balance | Borrower | 66,000 |  |  |
Aggregate outstanding balance of loans cancelled | $ 1,700,000,000 |  |  |
Expense on cancellation of loans | 50,000,000 |  |  |
One-time payment | $ 145,000,000 |  |  |
Regulatory expenses |  | $ 205,000,000 |  |
SLM BankCo [Member] | Indemnification Matters [Member] |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Reserve for estimated amounts and costs incurred |  |  |  | $ 0

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