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Education Loans - Education Loan Portfolio by Program (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
Accounts Notes And Loans Receivable [Line Items] |  |
Ending Balance of education loans | $ 54,827 | $ 62,250
Percentage to total education loans | 100.00% | 100.00%
Average Balance education loans | $ 59,654 | $ 69,707
Average Effective Interest Rate of education loans | 7.15% | 4.53%
FFELP Loans [Member] |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Ending Balance of education loans | $ 37,925 | $ 43,525
Stafford Loans [Member] | FFELP Loans [Member] |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Ending Balance of education loans | $ 13,564 | $ 15,691
Percentage to total education loans | 25.00% | 25.00%
Average Balance education loans | $ 14,949 | $ 17,475
Average Effective Interest Rate of education loans | 7.44% | 3.93%
Consolidation Loans [Member] | FFELP Loans [Member] |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Ending Balance of education loans | $ 24,361 | $ 27,834
Percentage to total education loans | 44.00% | 45.00%
Average Balance education loans | $ 26,242 | $ 31,708
Average Effective Interest Rate of education loans | 6.80% | 4.04%
Private Education Loans [Member] |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Ending Balance of education loans | $ 16,902 | $ 18,725
Percentage to total education loans | 31.00% | 30.00%
Average Balance education loans | $ 18,463 | $ 20,524
Average Effective Interest Rate of education loans | 7.42% | 5.82%

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- Definition Percentage to total student loans. + References No definition available. + Details
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