XML 64 R53.htm IDEA: XBRL DOCUMENT
v3.23.2

Allowance for Credit Losses - Loan Portfolio Stratified by Key Credit Quality Indicators (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022
% of Balance |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff | $ 114,134 | $ 106,999 | $ 210,216 | $ 191,065 |
Recoveries | 11,695 | 10,977 | 23,692 | 19,013 |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff | 102,439 | $ 96,022 | 186,524 | $ 172,052 |
Consumer Portfolio Segment | Student Loan |  |  |  |  |
% of Balance |  |  |  |  |
Current period gross charge-offs, Year 1 |  |  | (42) |  | $ (2,224)
Current period gross charge-offs, Year 2 |  |  | (9,040) |  | (25,698)
Current period gross charge-offs, Year 3 |  |  | (35,961) |  | (48,271)
Current period gross charge-offs, Year 4 |  |  | (25,581) |  | (62,071)
Current period gross charge-offs, Year 5 |  |  | (26,051) |  | (57,505)
Current period gross charge-offs, After Year 5 |  |  | (112,960) |  | (231,647)
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff |  |  | 209,635 |  | 427,416
Current period recoveries, Year 1 |  |  | 0 |  | 124
Current period recoveries, Year 2 |  |  | 646 |  | 1,841
Current period recoveries, Year 3 |  |  | 3,279 |  | 4,170
Current period recoveries, Year 4 |  |  | 2,541 |  | 5,556
Current period recoveries, Year 5 |  |  | 2,870 |  | 5,407
Current period recoveries, After Year 5 |  |  | 14,356 |  | 24,639
Recoveries |  |  | 23,692 |  | 41,737
Current period net charge-offs, Year 1 |  |  | (42) |  | (2,100)
Current period net charge-offs, Year 2 |  |  | (8,394) |  | (23,857)
Current period recoveries, Year 3 |  |  | (32,682) |  | (44,101)
Current period recoveries, Year 4 |  |  | (23,040) |  | (56,515)
Current period recoveries, Year 5 |  |  | (23,181) |  | (52,098)
Current period recoveries, After Year 5 |  |  | (98,604) |  | (207,008)
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff |  |  | 185,943 |  | 385,679
Total accrued interest by origination vintage, Year 1 | 39,186 |  | 39,186 |  | 142,915
Total accrued interest by origination vintage, Year 2 | 320,737 |  | 320,737 |  | 315,308
Total accrued interest by origination vintage, Year 3 | 304,663 |  | 304,663 |  | 207,858
Total accrued interest by origination vintage, Year 4 | 182,079 |  | 182,079 |  | 184,832
Total accrued interest by origination vintage, Year 5 | 153,744 |  | 153,744 |  | 116,211
Total accrued interest by origination vintage, After Year 5 | 275,332 |  | 275,332 |  | 210,438
Total accrued interest by origination vintage | 1,275,741 |  | 1,275,741 |  | 1,177,562
Consumer Portfolio Segment | Student Loan | With and without cosigners |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | 1,374,107 |  | 1,374,107 |  | 4,276,533
Year 2 | 5,481,115 |  | 5,481,115 |  | 4,547,159
Year 3 | 3,455,211 |  | 3,455,211 |  | 2,584,622
Year 4 | 2,071,289 |  | 2,071,289 |  | 2,172,660
Year 5 | 1,824,409 |  | 1,824,409 |  | 1,615,842
After Year 5 | 5,732,232 |  | 5,732,232 |  | 5,106,872
Loan type | $ 19,938,363 |  | $ 19,938,363 |  | $ 20,303,688
% of Balance |  |  |  |  |
Total in percent | 100.00% |  | 100.00% |  | 100.00%
Consumer Portfolio Segment | Student Loan | With cosigner |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 1,128,289 |  | $ 1,128,289 |  | $ 3,656,111
Year 2 | 4,760,539 |  | 4,760,539 |  | 3,941,921
Year 3 | 2,967,985 |  | 2,967,985 |  | 2,208,033
Year 4 | 1,750,797 |  | 1,750,797 |  | 1,853,619
Year 5 | 1,542,521 |  | 1,542,521 |  | 1,402,828
After Year 5 | 5,134,126 |  | 5,134,126 |  | 4,626,491
Loan type | $ 17,284,257 |  | $ 17,284,257 |  | $ 17,689,003
% of Balance |  |  |  |  |
Private education loans | 87.00% |  | 87.00% |  | 87.00%
Consumer Portfolio Segment | Student Loan | Without cosigner |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 245,818 |  | $ 245,818 |  | $ 620,422
Year 2 | 720,576 |  | 720,576 |  | 605,238
Year 3 | 487,226 |  | 487,226 |  | 376,589
Year 4 | 320,492 |  | 320,492 |  | 319,041
Year 5 | 281,888 |  | 281,888 |  | 213,014
After Year 5 | 598,106 |  | 598,106 |  | 480,381
Loan type | $ 2,654,106 |  | $ 2,654,106 |  | $ 2,614,685
% of Balance |  |  |  |  |
Private education loans | 13.00% |  | 13.00% |  | 13.00%
Consumer Portfolio Segment | Student Loan | FICO at Origination |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 1,374,107 |  | $ 1,374,107 |  | $ 4,276,533
Year 2 | 5,481,115 |  | 5,481,115 |  | 4,547,159
Year 3 | 3,455,211 |  | 3,455,211 |  | 2,584,622
Year 4 | 2,071,289 |  | 2,071,289 |  | 2,172,660
Year 5 | 1,824,409 |  | 1,824,409 |  | 1,615,842
After Year 5 | 5,732,232 |  | 5,732,232 |  | 5,106,872
Loan type | $ 19,938,363 |  | $ 19,938,363 |  | $ 20,303,688
% of Balance |  |  |  |  |
Total in percent | 100.00% |  | 100.00% |  | 100.00%
Consumer Portfolio Segment | Student Loan | FICO at Origination | Less than 670 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 107,391 |  | $ 107,391 |  | $ 326,991
Year 2 | 420,793 |  | 420,793 |  | 307,646
Year 3 | 240,208 |  | 240,208 |  | 158,606
Year 4 | 131,690 |  | 131,690 |  | 177,098
Year 5 | 151,540 |  | 151,540 |  | 143,674
After Year 5 | 504,422 |  | 504,422 |  | 439,587
Loan type | $ 1,556,044 |  | $ 1,556,044 |  | $ 1,553,602
% of Balance |  |  |  |  |
Private education loans at origination | 8.00% |  | 8.00% |  | 8.00%
Consumer Portfolio Segment | Student Loan | FICO at Origination | 670-699 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 204,117 |  | $ 204,117 |  | $ 593,216
Year 2 | 755,918 |  | 755,918 |  | 611,649
Year 3 | 465,841 |  | 465,841 |  | 356,541
Year 4 | 287,047 |  | 287,047 |  | 339,685
Year 5 | 285,693 |  | 285,693 |  | 259,142
After Year 5 | 977,653 |  | 977,653 |  | 878,426
Loan type | $ 2,976,269 |  | $ 2,976,269 |  | $ 3,038,659
% of Balance |  |  |  |  |
Private education loans at origination | 15.00% |  | 15.00% |  | 15.00%
Consumer Portfolio Segment | Student Loan | FICO at Origination | 700-749 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 438,522 |  | $ 438,522 |  | $ 1,336,765
Year 2 | 1,706,428 |  | 1,706,428 |  | 1,440,510
Year 3 | 1,094,180 |  | 1,094,180 |  | 834,819
Year 4 | 669,539 |  | 669,539 |  | 719,777
Year 5 | 607,938 |  | 607,938 |  | 537,680
After Year 5 | 1,932,404 |  | 1,932,404 |  | 1,722,068
Loan type | $ 6,449,011 |  | $ 6,449,011 |  | $ 6,591,619
% of Balance |  |  |  |  |
Private education loans at origination | 32.00% |  | 32.00% |  | 32.00%
Consumer Portfolio Segment | Student Loan | FICO at Origination | Greater than or equal to 750 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 624,077 |  | $ 624,077 |  | $ 2,019,561
Year 2 | 2,597,976 |  | 2,597,976 |  | 2,187,354
Year 3 | 1,654,982 |  | 1,654,982 |  | 1,234,656
Year 4 | 983,013 |  | 983,013 |  | 936,100
Year 5 | 779,238 |  | 779,238 |  | 675,346
After Year 5 | 2,317,753 |  | 2,317,753 |  | 2,066,791
Loan type | $ 8,957,039 |  | $ 8,957,039 |  | $ 9,119,808
% of Balance |  |  |  |  |
Private education loans at origination | 45.00% |  | 45.00% |  | 45.00%
Consumer Portfolio Segment | Student Loan | FICO Refreshed |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 1,374,107 |  | $ 1,374,107 |  | $ 4,276,533
Year 2 | 5,481,115 |  | 5,481,115 |  | 4,547,159
Year 3 | 3,455,211 |  | 3,455,211 |  | 2,584,622
Year 4 | 2,071,289 |  | 2,071,289 |  | 2,172,660
Year 5 | 1,824,409 |  | 1,824,409 |  | 1,615,842
After Year 5 | 5,732,232 |  | 5,732,232 |  | 5,106,872
Loan type | $ 19,938,363 |  | $ 19,938,363 |  | $ 20,303,688
% of Balance |  |  |  |  |
Total in percent | 100.00% |  | 100.00% |  | 100.00%
Consumer Portfolio Segment | Student Loan | FICO Refreshed | Less than 670 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 129,421 |  | $ 129,421 |  | $ 443,868
Year 2 | 597,699 |  | 597,699 |  | 461,589
Year 3 | 383,532 |  | 383,532 |  | 242,310
Year 4 | 212,612 |  | 212,612 |  | 237,105
Year 5 | 212,598 |  | 212,598 |  | 204,894
After Year 5 | 822,750 |  | 822,750 |  | 773,324
Loan type | $ 2,358,612 |  | $ 2,358,612 |  | $ 2,363,090
% of Balance |  |  |  |  |
Private education loans at origination | 12.00% |  | 12.00% |  | 12.00%
Consumer Portfolio Segment | Student Loan | FICO Refreshed | 670-699 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 200,879 |  | $ 200,879 |  | $ 594,118
Year 2 | 732,796 |  | 732,796 |  | 579,784
Year 3 | 421,987 |  | 421,987 |  | 284,244
Year 4 | 222,546 |  | 222,546 |  | 240,999
Year 5 | 197,829 |  | 197,829 |  | 173,754
After Year 5 | 635,210 |  | 635,210 |  | 564,344
Loan type | $ 2,411,247 |  | $ 2,411,247 |  | $ 2,437,243
% of Balance |  |  |  |  |
Private education loans at origination | 12.00% |  | 12.00% |  | 12.00%
Consumer Portfolio Segment | Student Loan | FICO Refreshed | 700-749 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 432,512 |  | $ 432,512 |  | $ 1,322,558
Year 2 | 1,632,162 |  | 1,632,162 |  | 1,378,910
Year 3 | 1,017,167 |  | 1,017,167 |  | 748,368
Year 4 | 579,151 |  | 579,151 |  | 628,060
Year 5 | 509,954 |  | 509,954 |  | 449,701
After Year 5 | 1,563,951 |  | 1,563,951 |  | 1,388,090
Loan type | $ 5,734,897 |  | $ 5,734,897 |  | $ 5,915,687
% of Balance |  |  |  |  |
Private education loans at origination | 29.00% |  | 29.00% |  | 29.00%
Consumer Portfolio Segment | Student Loan | FICO Refreshed | Greater than or equal to 750 |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 611,295 |  | $ 611,295 |  | $ 1,915,989
Year 2 | 2,518,458 |  | 2,518,458 |  | 2,126,876
Year 3 | 1,632,525 |  | 1,632,525 |  | 1,309,700
Year 4 | 1,056,980 |  | 1,056,980 |  | 1,066,496
Year 5 | 904,028 |  | 904,028 |  | 787,493
After Year 5 | 2,710,321 |  | 2,710,321 |  | 2,381,114
Loan type | $ 9,433,607 |  | $ 9,433,607 |  | $ 9,587,668
% of Balance |  |  |  |  |
Private education loans at origination | 47.00% |  | 47.00% |  | 47.00%
Consumer Portfolio Segment | Student Loan | Seasoning |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 1,374,107 |  | $ 1,374,107 |  | $ 4,276,533
Year 2 | 5,481,115 |  | 5,481,115 |  | 4,547,159
Year 3 | 3,455,211 |  | 3,455,211 |  | 2,584,622
Year 4 | 2,071,289 |  | 2,071,289 |  | 2,172,660
Year 5 | 1,824,409 |  | 1,824,409 |  | 1,615,842
After Year 5 | 5,732,232 |  | 5,732,232 |  | 5,106,872
Loan type | $ 19,938,363 |  | $ 19,938,363 |  | $ 20,303,688
% of Balance |  |  |  |  |
Total in percent | 100.00% |  | 100.00% |  | 100.00%
Consumer Portfolio Segment | Student Loan | Seasoning | 1-12 payments |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 708,493 |  | $ 708,493 |  | $ 2,448,884
Year 2 | 2,807,944 |  | 2,807,944 |  | 636,073
Year 3 | 444,729 |  | 444,729 |  | 384,334
Year 4 | 274,745 |  | 274,745 |  | 330,316
Year 5 | 236,836 |  | 236,836 |  | 235,878
After Year 5 | 446,584 |  | 446,584 |  | 424,636
Loan type | $ 4,919,331 |  | $ 4,919,331 |  | $ 4,460,121
% of Balance |  |  |  |  |
Seasoning based on monthly scheduled payments due from 1-12 payments | 25.00% |  | 25.00% |  | 22.00%
Consumer Portfolio Segment | Student Loan | Seasoning | 13-24 payments |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 0 |  | $ 0 |  | $ 0
Year 2 | 467,523 |  | 467,523 |  | 2,477,764
Year 3 | 1,781,078 |  | 1,781,078 |  | 255,510
Year 4 | 180,207 |  | 180,207 |  | 195,753
Year 5 | 195,356 |  | 195,356 |  | 166,045
After Year 5 | 526,126 |  | 526,126 |  | 455,782
Loan type | $ 3,150,290 |  | $ 3,150,290 |  | $ 3,550,854
% of Balance |  |  |  |  |
Seasoning based on monthly scheduled payments due from 13 - 24 payments | 16.00% |  | 16.00% |  | 18.00%
Consumer Portfolio Segment | Student Loan | Seasoning | 25-36 payments |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 0 |  | $ 0 |  | $ 0
Year 2 | 0 |  | 0 |  | 0
Year 3 | 255,314 |  | 255,314 |  | 1,366,398
Year 4 | 1,001,721 |  | 1,001,721 |  | 257,534
Year 5 | 121,822 |  | 121,822 |  | 126,223
After Year 5 | 513,211 |  | 513,211 |  | 489,157
Loan type | $ 1,892,068 |  | $ 1,892,068 |  | $ 2,239,312
% of Balance |  |  |  |  |
Seasoning based on monthly scheduled payments due from 25 - 36 payments | 9.00% |  | 9.00% |  | 11.00%
Consumer Portfolio Segment | Student Loan | Seasoning | 37-48 payments |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 0 |  | $ 0 |  | $ 0
Year 2 | 0 |  | 0 |  | 0
Year 3 | 0 |  | 0 |  | 127
Year 4 | 186,722 |  | 186,722 |  | 1,008,418
Year 5 | 864,585 |  | 864,585 |  | 224,805
After Year 5 | 499,560 |  | 499,560 |  | 451,102
Loan type | $ 1,550,867 |  | $ 1,550,867 |  | $ 1,684,452
% of Balance |  |  |  |  |
Seasoning based on monthly scheduled payments due from 37 - 48 payments | 8.00% |  | 8.00% |  | 8.00%
Consumer Portfolio Segment | Student Loan | Seasoning | More than 48 payments |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 0 |  | $ 0 |  | $ 0
Year 2 | 0 |  | 0 |  | 0
Year 3 | 0 |  | 0 |  | 0
Year 4 | 0 |  | 0 |  | 0
Year 5 | 112,729 |  | 112,729 |  | 643,611
After Year 5 | 3,211,222 |  | 3,211,222 |  | 2,830,285
Loan type | $ 3,323,951 |  | $ 3,323,951 |  | $ 3,473,896
% of Balance |  |  |  |  |
Seasoning based on monthly scheduled payments due from more than 48 payments | 17.00% |  | 17.00% |  | 17.00%
Consumer Portfolio Segment | Student Loan | Seasoning | Not yet in repayment |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Year 1 | $ 665,614 |  | $ 665,614 |  | $ 1,827,649
Year 2 | 2,205,648 |  | 2,205,648 |  | 1,433,322
Year 3 | 974,090 |  | 974,090 |  | 578,253
Year 4 | 427,894 |  | 427,894 |  | 380,639
Year 5 | 293,081 |  | 293,081 |  | 219,280
After Year 5 | 535,529 |  | 535,529 |  | 455,910
Loan type | $ 5,101,856 |  | $ 5,101,856 |  | $ 4,895,053
% of Balance |  |  |  |  |
Seasoning based on monthly scheduled payments due from not yet in repayment | 25.00% |  | 25.00% |  | 24.00%

X
- Definition Financing Receivable, Accrued Interest, Origination Interest, Originated Five or More Years before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAccruedInterestOriginationInterestOriginatedFiveOrMoreYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Accrued Interest, Origination Vintage, before Allowance for Credit Loss + References No definition available. + Details
Name: | slm_FinancingReceivableAccruedInterestOriginationVintageBeforeAllowanceForCreditLoss
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Accrued interest, Origination Vintage, Originated Four Years before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAccruedInterestOriginationVintageOriginatedFourYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Accrued Interest, Origination Vintage, Originated in Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAccruedInterestOriginationVintageOriginatedInCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Accrued Interest, Origination Vintage, Originated in Fiscal Year before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAccruedInterestOriginationVintageOriginatedInFiscalYearBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Accrued interest, Origination Vintage, Originated Three Years before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAccruedInterestOriginationVintageOriginatedThreeYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Accrued interest, Origination Vintage, Originated Two Years before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAccruedInterestOriginationVintageOriginatedTwoYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Writeoff, Originated Five Or More Years Before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterestWriteoffOriginatedFiveOrMoreYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Writeoff, Originated Four Years Before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterestWriteoffOriginatedFourYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Writeoff, Originated In Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterestWriteoffOriginatedInCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Writeoff, Originated In Fiscal Year Before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterestWriteoffOriginatedInFiscalYearBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Writeoff, Originated Three Years Before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterestWriteoffOriginatedThreeYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Writeoff, Originated Two Years Before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterestWriteoffOriginatedTwoYearsBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Recovery, Originated Five Or More Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossRecoveryOriginatedFiveOrMoreYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Recovery, Originated Four Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossRecoveryOriginatedFourYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Recovery, Originated In Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossRecoveryOriginatedInCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Recovery, Originated In Fiscal Year Before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossRecoveryOriginatedInFiscalYearBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Recovery, Originated Three Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossRecoveryOriginatedThreeYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Recovery, Originated Two Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossRecoveryOriginatedTwoYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Originated Five Or More Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossWriteoffAfterRecoveryOriginatedFiveOrMoreYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Originated Four Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossWriteoffAfterRecoveryOriginatedFourYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Originated In Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossWriteoffAfterRecoveryOriginatedInCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Originated In Fiscal Year Before Latest Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossWriteoffAfterRecoveryOriginatedInFiscalYearBeforeLatestFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Originated Three Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossWriteoffAfterRecoveryOriginatedThreeYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery, Originated Two Years Before Current Fiscal Year + References No definition available. + Details
Name: | slm_FinancingReceivableAllowanceForCreditLossWriteoffAfterRecoveryOriginatedTwoYearsBeforeCurrentFiscalYear
Namespace Prefix: | slm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percent Of Balance + References No definition available. + Details
Name: | slm_PercentOfBalanceAbstract
Namespace Prefix: | slm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent of private loans + References No definition available. + Details
Name: | slm_PercentOfPrivateLoans
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Private Education Loans At Origination + References No definition available. + Details
Name: | slm_PrivateEducationLoansAtOrigination
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Private education loans gross in percent. + References No definition available. + Details
Name: | slm_PrivateEducationLoansGrossPercentage
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Seasoning based on monthly scheduled payments due from more than forty eight payments in percent + References No definition available. + Details
Name: | slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromMoreThanFortyEightPaymentsInPercent
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Seasoning based on monthly scheduled payments due from not yet in repayment in percent + References No definition available. + Details
Name: | slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromNotYetInRepaymentInPercent
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Seasoning based on monthly scheduled payments due from one to twelve payments in percent. + References No definition available. + Details
Name: | slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromOneToTwelvePaymentsInPercent
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Seasoning based on monthly scheduled payments due from thirteen to twenty four payments in percent. + References No definition available. + Details
Name: | slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromThirteenToTwentyFourPaymentsInPercent
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Seasoning based on monthly scheduled payments due from thirty seven to forty eight payments in percent. + References No definition available. + Details
Name: | slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromThirtySevenToFortyEightPaymentsInPercent
Namespace Prefix: | slm_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Seasoning based on monthly scheduled payments due from thirteen to twenty four payments in percent + References No definition available. + Details
Name: | slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromTwentyFiveToThirtySixPaymentsInPercent
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 No definition available. + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). 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_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoffAfterRecovery
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-5 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated in current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable originated two years prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest of financing receivable originated in fiscal year prior to current fiscal year. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-6 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_StudentLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | slm_CreditQualityIndicatorsAxis=slm_CosignerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | slm_CreditQualityIndicatorsAxis=slm_WithCosignerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | slm_CreditQualityIndicatorsAxis=slm_WithoutCosignerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | slm_CreditQualityIndicatorsAxis=slm_SchoolFicoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditScoreFicoAxis=slm_FICOscorelessthan670Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditScoreFicoAxis=slm_FICOscore670699Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditScoreFicoAxis=slm_FICOscore700749Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditScoreFicoAxis=slm_FICOscoregreaterthan750Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | slm_CreditQualityIndicatorsAxis=slm_SchoolFICORefreshedAmountsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | slm_CreditQualityIndicatorsAxis=slm_RepaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromOneToTwelvePaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromThirteenToTwentyFourPaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromTwentyFiveToThirtySixPaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromThirtySevenToFortyEightPaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromMoreThanFortyEightPaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=slm_SeasoningBasedOnMonthlyScheduledPaymentsDueFromNotYetInRepaymentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |