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

Debt Instrument, Unused Borrowing Capacity Fee, Percentage

+ 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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Balance Type:	credit
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- Definition

Line of Credit Facility, Percent Outstanding of Borrowing Capacity

+ References

No definition available.

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- Definition

Line of Credit, Required Ownership Interest

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Loans Securitized or Asset-Backed Financing Arrangement, Ownership Interest, 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://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

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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.

+ Details

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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.

+ 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

+ Details

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Period Type:	instant

- Definition

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

+ References

+ Details

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Period Type:	instant

- 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.

+ References

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-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
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-Paragraph 5
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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).

+ 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

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Borrowings - Additional Information (Details) - USD ($)			6 Months Ended	12 Months Ended
Borrowings - Additional Information (Details) - USD ($)	May 26, 2016	Feb. 25, 2016	Jun. 30, 2016	Dec. 31, 2015	Dec. 19, 2014
Line of Credit Facility [Line Items]
Short-term borrowings			$ 0	$ 500,175,000
Estimated weighted average life of student loans (in years)			6 years	6 years 2 months 12 days
Uncommitted federal funds			$ 100,000,000
Lendable value of collateral			2,800,000,000	$ 1,700,000,000
Class A Notes
Line of Credit Facility [Line Items]
Amount of loan securitization sold to third parties	$ 501,000,000
Proceeds from loan securitization sold to third parties	$ 501,000,000
Estimated weighted average life of student loans (in years)	4 years 3 days
Class B Notes
Line of Credit Facility [Line Items]
Ownership interest percentage	100.00%
Amount of ownership interest in loan securitization	$ 50,000,000
ABCP borrowings
Line of Credit Facility [Line Items]
Short-term borrowings			0	$ 500,175,000
Loans pledged as collateral			$ 0
Contractual maturity			2 years
Contractual maturity term, revolving period			1 year
Contractual maturity term, amortization period			1 year
ABCP borrowings \| Commercial Paper
Line of Credit Facility [Line Items]
Private asset backed commercial paper education loan funding facility		$ 750,000,000.0			$ 750,000,000.0
Ownership interest percentage in loan facility					5.00%
Required ownership interest					$ 37,500,000
Funds available for Private Education Loan originations					$ 712,500,000
Financing cost percentage of unused borrowing capacity				0.40%
Ownership interest percentage			100.00%
Private Education Loans
Line of Credit Facility [Line Items]
Loans pledged as collateral			$ 583,000,000
Total loan amount securitized at inception for the 2016 on-balance sheet term securitization	551,000,000
Proceeds from loan securitization sold to third parties	$ 501,000,000
Residual Certificates
Line of Credit Facility [Line Items]
Ownership interest percentage	100.00%
LIBOR \| Class A Notes
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.38%
LIBOR \| ABCP borrowings \| Commercial Paper
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.00%		0.80%
Minimum \| ABCP borrowings \| Commercial Paper
Line of Credit Facility [Line Items]
Financing cost percentage of unused borrowing capacity		0.35%
Maximum \| ABCP borrowings \| Commercial Paper
Line of Credit Facility [Line Items]
Financing cost percentage of unused borrowing capacity		0.45%