Delinquencies as a percentage of loans in repayment.

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Loan Status Forbearance, Period of One-Time Disaster Forbearance

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Loan status forbearance recorded investment.

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Loan status in school grace and deferment recorded investment.

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No definition available.

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- Definition

Total loans.

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Total loans, gross

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Loans in forbearance as a percentage of loans in repayment and forbearance.

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No definition available.

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Total loans in repayment.

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Loans in repayment and percentage of each status.

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Loans in repayment current in percentage.

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Total loans in repayment, in percentage.

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Net unamortized premium or discount on loans receivable.

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Percentage of loans in repayment.

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No definition available.

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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.

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Percent of financing receivables past due.

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Financing receivables that are current.

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

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-Name Accounting Standards Codification

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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Allowance for Loan Losses - Age Analysis of Past Due Loans Delinquencies (Detail) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
	Jun. 01, 2015	Jun. 30, 2015	Dec. 31, 2014	Mar. 31, 2015	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
Loans in repayment and percentage of each status:
Allowance for loan losses		$ (91,866)	$ (83,842)	$ (89,805)	$ (60,527)	$ (77,634)	$ (68,081)
Private Education Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans in-school/grace/deferment		3,304,171	3,027,143
Loans in forbearance		342,121	135,018
Loans in repayment and percentage of each status:
Loans current		5,570,389	5,045,600
Total loans in repayment		5,666,645	5,149,215
Total loans, gross		9,312,937	8,311,376
Deferred origination costs		19,632	13,845
Total loans		9,332,569	8,325,221
Allowance for loan losses		(87,310)	(78,574)	$ (85,236)	$ (54,315)	$ (71,453)	$ (61,763)
Total loans, net		$ 9,245,259	$ 8,246,647
Loans current, in percentage		98.30%	98.00%
Total loans in repayment, in percentage		100.00%	100.00%
Percentage of loans in repayment		60.80%	62.00%
Delinquencies as a percentage of loans in repayment		1.70%	2.00%
Loans in forbearance as a percentage of loans in repayment and forbearance		5.70%	2.60%
One-time disaster forbearance period	2 months
Loans delinquent 31-60 days \| Private Education Loans
Loans in repayment and percentage of each status:
Loans delinquent		$ 57,884	$ 63,873
Loans delinquent, in percentage		1.00%	1.20%
Loans delinquent 61-90 days \| Private Education Loans
Loans in repayment and percentage of each status:
Loans delinquent		$ 28,306	$ 29,041
Loans delinquent, in percentage		0.50%	0.60%
Loans delinquent greater than 90 days \| Private Education Loans
Loans in repayment and percentage of each status:
Loans delinquent		$ 10,066	$ 10,701
Loans delinquent, in percentage		0.20%	0.20%