Deferred Tax Assets, Remaining Balance of Indemnification Receivable In Connection with The Spin-Off

No definition available.

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Namespace Prefix:	slm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Minimum Days Past Due That Company May Require Spin Off Company to Purchase Loans

+ References

No definition available.

+ Details

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- Definition

Period of Hardship Forbearance

+ References

No definition available.

+ Details

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Namespace Prefix:	slm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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=121570589&loc=d3e107425-111719

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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=121570589&loc=d3e107314-111719

+ Details

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Balance Type:	debit
Period Type:	instant

- 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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- Details

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Period Type:

Arrangements with Navient Corporation (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2020	Mar. 31, 2020	Apr. 30, 2014
Related Party Transaction [Line Items]
Remaining balance of indemnification receivable in connection with the spin-off		$ 7		$ 27
Minimum days past due for spin off loan purchase		90 days
Period of hardship forbearance		6 months
Discontinued Operations, Disposed of by Sale
Related Party Transaction [Line Items]
Split Loans portfolio sales price	$ 43		$ 43
Gains on sales of loans, net	$ 2