Debt Instrument, Unused Borrowing Capacity Fee, Percentage

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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Period Type:	instant

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107314-111719

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	credit
Period Type:	instant

- 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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107314-111719

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Subsequent Events (Details) - USD ($)					12 Months Ended
Subsequent Events (Details) - USD ($)	Feb. 22, 2017	Feb. 08, 2017	Feb. 25, 2016	Jul. 30, 2015	Dec. 31, 2015	Oct. 12, 2016	Jul. 21, 2016	May 26, 2016	Oct. 27, 2015	Apr. 23, 2015	Dec. 19, 2014
Private Education Loans
Subsequent Event [Line Items]
Loans sold to third parties				$ 631,000,000					$ 701,000,000	$ 738,000,000
Private education loan term accounted for as a secured financing				714,000,000		$ 674,000,000	$ 657,000,000	$ 551,000,000
Gross profit raised from loans sold to third parties				$ 623,000,000
Residual Certificates
Subsequent Event [Line Items]
Ownership interest percentage on asset-backed financing				100.00%			100.00%	100.00%
Subsequent Event \| Private Education Loans
Subsequent Event [Line Items]
Loans sold to third parties		$ 772,000,000
Private education loan term accounted for as a secured financing		$ 772,000,000
Subsequent Event \| Residual Certificates
Subsequent Event [Line Items]
Ownership interest percentage on asset-backed financing		100.00%
Subsequent Event \| Private Education Loans, 2017 Term A
Subsequent Event [Line Items]
Gross profit raised from loans sold to third parties		$ 768,000,000
Commercial Paper \| ABCP borrowings
Subsequent Event [Line Items]
Private education loan funding			$ 750,000,000.0								$ 750,000,000.0
Unused borrowing capacity fee (as a percent)					0.40%
Commercial Paper \| Subsequent Event \| ABCP borrowings
Subsequent Event [Line Items]
Private education loan funding	$ 750,000,000.0
Minimum \| Commercial Paper \| ABCP borrowings
Subsequent Event [Line Items]
Unused borrowing capacity fee (as a percent)			0.35%
Minimum \| Commercial Paper \| Subsequent Event \| ABCP borrowings
Subsequent Event [Line Items]
Unused borrowing capacity fee (as a percent)	0.35%
Maximum \| Commercial Paper \| ABCP borrowings
Subsequent Event [Line Items]
Unused borrowing capacity fee (as a percent)			0.45%
Maximum \| Commercial Paper \| Subsequent Event \| ABCP borrowings
Subsequent Event [Line Items]
Unused borrowing capacity fee (as a percent)	0.45%
London Interbank Offered Rate (LIBOR) \| Commercial Paper \| ABCP borrowings
Subsequent Event [Line Items]
Basis spread on variable rate			0.90%		0.80%
London Interbank Offered Rate (LIBOR) \| Commercial Paper \| Subsequent Event \| ABCP borrowings
Subsequent Event [Line Items]
Basis spread on variable rate	0.90%