Debt instrument maturities month year.

No definition available.

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- Definition

Total unencumbered loans at the balance sheet date.

+ References

No definition available.

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- Definition

Amount of assets pledged to secure a debt instrument.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Borrowings - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Outstanding borrowings under facility	$ 57,628	$ 66,896
Issuance of unsecured debt	1,000	$ 0	$ 1,300
FFELP Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	1,900
Assets securing facility	2,100
Maximum unused capacity	408
Unencumbered Loans	$ 92
FFELP Loan ABCP Facilities [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Facility maturity date	2024-11
FFELP Loan ABCP Facilities [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Facility maturity date	2025-04
FFELP Loan \| Asset-backed Securities, Securitized Loans and Receivables [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	$ 181
Private Education Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	2,100
Assets securing facility	2,500
Maximum unused capacity	1,700
Unencumbered Loans	$ 1,100
Private Education Loan ABCP Facilities [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Facility maturity date	2024-06
Private Education Loan ABCP Facilities [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Facility maturity date	2025-06
Private Education Loan Repurchase Facilities \| Asset-backed Securities, Securitized Loans and Receivables [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	$ 400