Estimated weighted average life of student loans.

No definition available.

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- Definition

Percent of Private Loans indexed to LIBOR

+ References

No definition available.

+ Details

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- Definition

Tier One of Government Guarantee

+ References

No definition available.

+ Details

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- Definition

Tier Three of Government Guarantee

+ References

No definition available.

+ Details

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- Definition

Tier Two of Government Guarantee

+ 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

Reflects the net positive or negative amount derived from subtracting from net proceeds of sale and the carrying amounts, net of allocated reserves, of financial assets transferred to third parties in transactions that qualify for sales treatment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107425-111719

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- Definition

This is the result of the principal amount outstanding of total loans managed or securitized less securitized loans and loans that are in the process of being securitized.

+ 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)
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107314-111719

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Loans Held for Investment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Jul. 01, 2006	Jun. 30, 2006	Sep. 30, 1993
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percent of private loans indexed to LIBOR	69.00%			69.00%		77.00%
Gain on sale of portfolio split loans	$ 0		$ 0	$ 2,060	$ 0
Tier 1 of government guarantee (in percentage)	97.00%			97.00%			97.00%
Tier 2 of government guarantee (in percentage)								98.00%
Tier 3 of government guarantee (in percentage)									100.00%
Estimated weighted average life of student loans (in years)				5 years 4 months 24 days		5 years 6 months
Discontinued Operations, Disposed of by Sale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio split loans sold		$ 43,000
Gain on sale of portfolio split loans		$ 2,000