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Loans and Leases Receivable, Forbearance Period after Grace Period

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Loans and Leases Receivable, Period After Grace Period for Forbearance Allowance

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Loans and Leases Receivable, Period of Forbearance

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Loans and Leases Receivable, Period of Forbearance Within Twenty-Four Month Period to be Classified as TDR

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Loans And Leases Receivable, Temporary Interest Rate Reduction, Financial Difficulty Status

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Loans and Leases Receivable, Impaired, Loans Granted Forbearance Qualified as Trouble Debt Restructuring

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Percentage Of Private Education Loans Related To Borrowers In School, Grace or Deferment

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Percentage Reimbursement On All Qualifying Default Claims Period One

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Percentage Reimbursement On All Qualifying Default Claims Period Three

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Percentage Reimbursement On All Qualifying Ffelp Default Claims Period Two

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Period Of Deferment For Adoption Of New Accounting Pronouncements

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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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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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The number of positions eliminated during the period as a result of restructuring activities.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Significant Accounting Policies - Additional Information (Details) $ in Thousands			3 Months Ended		9 Months Ended
	May 31, 2020 USD ($)	Jan. 01, 2020	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) numberOfInvestments	Sep. 30, 2019 USD ($)	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Percentage of Private Education Loans related to borrowers in school, grace or deferment			27.00%		27.00%		25.00%
Interest rate offered to borrowers facing financial difficulty			4.00%		4.00%
Period of forbearance period to be classified as TDR					3 months
Period of forbearance					24 months
Period after grace period for forbearance allowance for loans					9 months
Forbearance period after grace period for loans					6 months
Percentage of loans granted forbearance (as a percentage)			47.00%		47.00%		50.00%
Percentage reimbursement on all qualifying default claims period two (as a percentage)			97.00%		97.00%
Percentage reimbursement on all qualifying default claims period one (as a percentage)			98.00%		98.00%
Percentage reimbursement on all qualifying default claims period three (as a percentage)			100.00%		100.00%
Variable rate			105.00%		105.00%
Gain on sale of Upromise subsidiary	$ 11,000				$ 11,331	$ 0
Restructuring expenses			$ 24,127	$ 0	$ 24,127	$ 0
Restructuring expenses related to severance benefits			20,000
Other related costs			$ 4,000
Positions eliminated \| numberOfInvestments					165
Workforce eliminated					9.00%
Accounting Standards Update 2016-13
Financing Receivable, Impaired [Line Items]
Period of deferment		2