Estimated weighted average life of student loans.

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- Definition

Loans Pledged As Collateral, Capitalized Interest

+ References

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- Definition

Loans Pledged As Collateral, Principal Amount

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No definition available.

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- Definition

Loans Securitized or Asset-Backed Financing Arrangement, Ownership Interest, Percentage

+ References

No definition available.

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- Definition

Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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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).

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- Definition

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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Borrowings - Long Term Borrowings (Details) - USD ($)					12 Months Ended
Borrowings - Long Term Borrowings (Details) - USD ($)	Aug. 12, 2020	Feb. 12, 2020	Jun. 12, 2019	Mar. 13, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Oct. 29, 2020	Apr. 05, 2017
Debt Instrument [Line Items]
Total Issued					$ 1,343,000,000	$ 1,110,000,000
Unsecured debt issued					$ 495,000,000	$ 0	$ 0
Estimated weighted average life of student loans					5 years 4 months 24 days	5 years 4 months 24 days
Senior Unsecured Notes Due April 5, 2022 \| Unsecured Debt
Debt Instrument [Line Items]
Total Issued					$ 199,000,000				$ 200,000,000
Interest rate									5.125%
Senior Unsecured Notes Due October 29, 2025 \| Unsecured Debt
Debt Instrument [Line Items]
Total Issued					494,000,000			$ 500,000,000
Interest rate								4.20%
Private Education Loans 2020 Term A
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing		$ 636,000,000
Loans sold to third parties		636,000,000
Unsecured debt issued		$ 634,000,000
Loans pledged as collateral					605,000,000
Principal amount of collateral					567,000,000
Capitalized interest					38,000,000
Ownership interest percentage on asset-backed financing		100.00%
Estimated weighted average life of student loans		4 years 2 months 4 days
Private Education Loans 2020 Term A \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		0.88%
Private Education Loans 2020 Term B
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing	$ 707,000,000
Loans sold to third parties	707,000,000
Unsecured debt issued	$ 705,000,000
Loans pledged as collateral					748,000,000
Principal amount of collateral					701,000,000
Capitalized interest					47,000,000
Ownership interest percentage on asset-backed financing	100.00%
Estimated weighted average life of student loans	4 years 1 month 20 days
Private Education Loans 2020 Term B \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	1.30%
Private Education Loans 2019 Term A
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing				$ 453,000,000
Loans sold to third parties				453,000,000
Unsecured debt issued				$ 451,000,000
Loans pledged as collateral					377,000,000
Principal amount of collateral					355,000,000
Capitalized interest					22,000,000
Ownership interest percentage on asset-backed financing				100.00%
Estimated weighted average life of student loans				4 years 3 months 3 days
Private Education Loans 2019 Term A \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate				92.00%
Private Education Loans 2019 Term B
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing			$ 657,000,000
Loans sold to third parties			657,000,000
Unsecured debt issued			$ 655,000,000
Loans pledged as collateral					578,000,000
Principal amount of collateral					542,000,000
Capitalized interest					$ 36,000,000
Ownership interest percentage on asset-backed financing			100.00%
Estimated weighted average life of student loans			4 years 4 months 28 days
Private Education Loans 2019 Term B \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate			1.01%