Contractual Maturity

No definition available.

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- Definition

Debt Instrument, Contractual Maturity, Term, Amortization Period

+ References

No definition available.

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- Definition

Debt Instrument, Contractual Maturity, Term, Revolving Period

+ References

No definition available.

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- Definition

Estimated weighted average life of student loans.

+ References

No definition available.

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- Definition

Lendable value of collateral

+ References

No definition available.

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- Definition

Loans Pledged As Collateral, Capitalized Interest

+ References

No definition available.

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- Definition

Loans Pledged As Collateral, Principal Amount

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Ownership Interest Percentage

+ References

No definition available.

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- Definition

Uncommitted Federal Funds

+ References

No definition available.

+ Details

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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.

+ 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)(1)
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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- Definition

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

+ References

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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.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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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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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Borrowings - Additional Information (Details) - USD ($)								12 Months Ended
Borrowings - Additional Information (Details) - USD ($)	Feb. 12, 2020	Jun. 12, 2019	Mar. 13, 2019	Feb. 20, 2019	Sep. 19, 2018	Jun. 20, 2018	Mar. 21, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Feb. 19, 2020	Apr. 05, 2017
Debt Instrument [Line Items]
Amount drawn and outstanding under ABCP facility								$ 289,230,000	$ 0
Total Issued								1,110,000,000	1,900,500,000
Unsecured debt issued								$ 0	$ 0	$ 197,000,000
Estimated weighted average life of student loans								5 years 4 months 24 days	5 years 5 months
Discretionary uncommitted federal funds line of credit								$ 125,000,000
Lendable value of collateral								3,200,000,000	$ 3,100,000,000
Unsecured Debt
Debt Instrument [Line Items]
Amount drawn and outstanding under ABCP facility								0	0
ABCP borrowings
Debt Instrument [Line Items]
Amount drawn and outstanding under ABCP facility								$ 289,230,000	0
Contractual maturity related to ABCP facility								2 years
Revolving period of contractual maturity								1 year
Amortization period of contractual maturity								1 year
Senior Unsecured Notes Due April 5, 2022 \| Unsecured Debt
Debt Instrument [Line Items]
Total Issued								$ 198,000,000				$ 200,000,000
Interest rate												5.125%
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
Ownership interest percentage on asset-backed financing			100.00%
Unsecured debt issued			$ 451,000,000
Loans pledged as collateral								445,000,000
Principal amount of collateral								417,000,000
Capitalized interest								28,000,000
Class A and B Notes
Debt Instrument [Line Items]
Estimated weighted average life of student loans		4 years 4 months 28 days	4 years 3 months 3 days		4 years 3 months 25 days	4 years 4 months 24 days	4 years 5 months 4 days
Class A and B Notes \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		1.01%	92.00%		0.77%	0.76%	0.78%
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
Ownership interest percentage on asset-backed financing		100.00%
Unsecured debt issued		$ 655,000,000
Loans pledged as collateral								666,000,000
Principal amount of collateral								625,000,000
Capitalized interest								41,000,000
Private Education Loans 2018 Term A
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing							$ 670,000,000
Loans sold to third parties							$ 670,000,000
Ownership interest percentage on asset-backed financing							100.00%
Unsecured debt issued							$ 668,000,000
Loans pledged as collateral								588,000,000
Principal amount of collateral								553,000,000
Capitalized interest								35,000,000
Private Education Loans 2018 Term B
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing						$ 687,000,000
Loans sold to third parties						$ 687,000,000
Ownership interest percentage on asset-backed financing						100.00%
Unsecured debt issued						$ 683,000,000
Loans pledged as collateral								623,000,000
Principal amount of collateral								585,000,000
Capitalized interest								38,000,000
Private Education Loans 2018 Term C
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing					$ 544,000,000
Loans sold to third parties					$ 544,000,000
Ownership interest percentage on asset-backed financing					100.00%
Unsecured debt issued					$ 541,000,000
Loans pledged as collateral								502,000,000
Principal amount of collateral								471,000,000
Capitalized interest								31,000,000
ABS Transactions
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing										$ 3,900,000,000
Private Education Loans
Debt Instrument [Line Items]
Private education loan term accounted for as a secured financing								2,700,000,000
Principal amount of collateral								2,600,000,000
Capitalized interest								115,000,000
Subsequent Event \| Class A and B Notes
Debt Instrument [Line Items]
Estimated weighted average life of student loans	4 years 2 months 4 days
Subsequent Event \| Class A and B Notes \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	0.88%
Commercial Paper \| ABCP borrowings
Debt Instrument [Line Items]
Private education loan funding				$ 750,000,000
Ownership interest percentage				100.00%
Amount drawn and outstanding under ABCP facility								$ 289,000,000	$ 0
Commercial Paper \| Subsequent Event \| ABCP borrowings
Debt Instrument [Line Items]
Private education loan funding											$ 2,000,000,000