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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.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Reflects the carrying amount of loans and leases for which agreements to acquire or dispose exist.

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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.

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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

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- Definition

Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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- Definition

Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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Loans Receivable and Allowance for Loan Losses - Loans Receivable (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended
	May 01, 2019	Nov. 07, 2019	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross				$ 21,206,948		$ 22,520,498
Loan discount, net of unamortized loan premiums and deferred origination costs, and non-accretable discount				(36,483)		(53,572)
Allowance for loan losses				(66,417)	$ (62,591)	(60,388)	$ (60,217)	$ (53,715)	$ (54,590)
Loans receivable				21,071,441		22,377,142
Non-accretable discount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan discount, net of unamortized loan premiums and deferred origination costs, and non-accretable discount				(32,607)		(29,396)
Federally insured loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross				20,695,837		22,155,896
Allowance for loan losses				(37,676)	(39,056)	(42,310)	(43,053)	(37,263)	(38,706)
Federally insured loans \| Stafford and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross				4,720,338		4,969,667
Federally insured loans \| Consolidation
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross				15,975,499		17,186,229
Private education loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross				189,912		225,975
Allowance for loan losses				(9,882)	(10,157)	(10,838)	(11,253)	(11,664)	(12,629)
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, gross				321,199		138,627
Allowance for loan losses				$ (18,859)	$ (13,378)	$ (7,240)	$ (5,911)	$ (4,788)	$ (3,255)
Consumer loans \| Financing receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold (par value)	$ 47,700
Gain on sale of loan	$ 1,700
Beneficial interest received as partial consideration	11.00%
Consumer loans \| Financing receivable \| Forecast
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain on sale of loan			$ 15,500
Consumer loans \| Financing receivable \| Subsequent event
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold (par value)		$ 179,300
Beneficial interest received as partial consideration		29.00%