XML 60 R47.htm IDEA: XBRL DOCUMENT v3.25.1

Allowance for Credit Losses and Unfunded Loan Commitments - Narrative (Details)	3 Months Ended			9 Months Ended	12 Months Ended		18 Months Ended
	Mar. 31, 2025 USD ($) payment	Jun. 30, 2024	Mar. 31, 2024 USD ($)	Sep. 30, 2023 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Mar. 31, 2025 USD ($)	Jul. 01, 2006
Accounts, Notes, Loans and Financing Receivable [Line Items]
Monthly payment that is smaller than the interest accrued on the loan in that month	$ 25
Financing receivable allowance period increase (decrease)	$ 11,000,000
Loan sale reduction to provision			$ 133,204,000	$ 133,000,000
Criteria for loans to be considered as nonperforming (greater than)	90 days
Tier 1 of government guarantee (at least)	97.00%				97.00%		97.00%	97.00%
Maximum amount of forbearance granted	12 months
Number of monthly payments required by a borrower between successive grants of forbearance | payment	12
Defaulted Amount	$ 143,663,000				$ 867,295,000	$ 1,001,410,000
Threshold period for payment default	60 days
Financing receivable, modified in period, subsequently charged off, amount	$ 18,500,000					40,400,000	$ 50,000,000
Period of loans past due that have accrued interest	90 days
Private Education Loans | Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financial receivable, excluding accrued interest, modified, accumulated						6,600,000
Financial receivable, excluding accrued interest, modified in period, to total financing receivables, percentage		0.03%
Financing receivable, modified, weighted average term increase from modification		6 years 9 months 18 days
Loan delinquent 30-59 days
Accounts, Notes, Loans and Financing Receivable [Line Items]
Defaulted Amount	$ 43,323,000				76,207,000	77,446,000
Loan delinquent, current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Defaulted Amount	48,710,000				692,649,000	826,007,000
Loan delinquent 60-89 days
Accounts, Notes, Loans and Financing Receivable [Line Items]
Defaulted Amount	26,691,000				48,976,000	43,484,000
Loan delinquent 90 days or greater past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Defaulted Amount	24,939,000				49,463,000	54,473,000
Private Education Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan sale reduction to provision	116,459,000		$ 133,204,000
Loans sold	2,000,000,000			$ 2,100,000,000
Defaulted Amount	$ 145,275,000				$ 900,913,000	$ 1,035,055,000
Threshold period when delinquent loans are written off	120 days
Financing receivable, modified in period, subsequently charged off, amount	$ 18,500,000
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increments in which forbearance is granted	2 months
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increments in which forbearance is granted	1 month

X

- Definition

Criteria for loans to be considered as nonperforming.

+ References

No definition available.

+ Details

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

X

- Definition

Financing Receivable And Off-Balance Sheet, Excluding Accrued Interest, Before Allowance For Credit Loss, Loan Sold

+ References

No definition available.

+ Details

Name:	slm_FinancingReceivableAndOffBalanceSheetExcludingAccruedInterestBeforeAllowanceForCreditLossLoanSold
Namespace Prefix:	slm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Financing Receivable, Increments In Which Forbearance Is Granted

+ References

No definition available.

+ Details

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

X

- Definition

Financing Receivable, Modified in Period, Subsequently Charged Off, Amount

+ References

No definition available.

+ Details

Name:	slm_FinancingReceivableModifiedInPeriodSubsequentlyChargedOffAmount
Namespace Prefix:	slm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Financing Receivable, Month Limit On Forbearance Granted, Life Of Loan

+ References

No definition available.

+ Details

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

X

- Definition

Financing Receivable, Number Of Monthly Payments Required Between Forbearance Grants

+ References

No definition available.

+ Details

Name:	slm_FinancingReceivableNumberOfMonthlyPaymentsRequiredBetweenForbearanceGrants
Namespace Prefix:	slm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Financing Receivable, Threshold Period For Payment Default

+ References

No definition available.

+ Details

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

X

- Definition

Fixed-Pay Loan, Monthly Payment Amount, Below Monthly Accrued Interest

+ References

No definition available.

+ Details

Name:	slm_FixedPayLoanMonthlyPaymentAmountBelowMonthlyAccruedInterest
Namespace Prefix:	slm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Period of Loans Past Due That Have Accrued Interest

+ References

No definition available.

+ Details

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

X

- Definition

Threshold Period Past Due For Write-off Of Financing Receivable

+ References

No definition available.

+ Details

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

X

- Definition

Tier One of Government Guarantee

+ References

No definition available.

+ Details

Name:	slm_TierOneofGovernmentGuarantee
Namespace Prefix:	slm_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

X

- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

+ Details

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from sale of loan. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossLoanSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Accumulated amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestModifiedAccumulated
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

Name:	us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-33

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

Name:	us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

+ Details

Name:	us-gaap_FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=slm_PrivateEducationLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=us-gaap_ExtendedMaturityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables30To59DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetNotPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables60To89DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivablesByIndustryOfCounterpartyTypeAxis=slm_PrivateEducationLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: