Private Education Loans - Schedule of Information Regarding Aggregate Changes in Accretable Yield (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
PEAKS Trust Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of period	$ 70,580	$ 0
Additions resulting from the PEAKS/CUSO Consolidation	0	100,953
Accretion	(11,471)	(12,996)
Reclassification from nonaccretable difference and changes in expected cash flows	(7,290)	(17,377)
Balance at end of period	51,819	70,580
PEAKS Trust Student Loans [Member] \| Analogy [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of period	42,274	0
Additions resulting from the PEAKS/CUSO Consolidation	0	58,843
Accretion	(6,700)	(7,243)
Reclassification from nonaccretable difference and changes in expected cash flows	(2,920)	(9,326)
Balance at end of period	32,654	42,274
CUSO Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of period	0
Additions resulting from the PEAKS/CUSO Consolidation	12,498
Accretion	(699)
Reclassification from nonaccretable difference and changes in expected cash flows	(71)
Balance at end of period	11,728
CUSO Student Loans [Member] \| Analogy [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of period	0
Additions resulting from the PEAKS/CUSO Consolidation	5,651
Accretion	(333)
Reclassification from nonaccretable difference and changes in expected cash flows	539
Balance at end of period	$ 5,857

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Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

+ Details

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- Definition

Amount of decrease from accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

+ Details

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- Definition

Amount of additions to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

+ Details

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- Definition

Amount of reclassification (to) from nonaccretable difference (from) to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

+ Details

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- Details

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- Details

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