v3.26.1
Loans and allowance for loan losses - Summary of loans in Accrual and Nonaccrual Status (Detail) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one $ 15,481   $ 15,481   $ 23,922
Year two 21,126   21,126   14,450
Year three 12,538   12,538   11,389
Year four 9,860   9,860   14,171
Year five 12,420   12,420   9,181
Prior 33,998   33,998   28,808
Total [1] 143,193   143,193   138,702
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Year one     5    
Year two     35    
Year three     50    
Year four     41    
Year five     26    
Prior     64    
Total 138 $ 156 291 $ 316  
Residential real estate          
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Total 2 1 3 3  
Consumer          
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Total 82 $ 73 170 $ 159  
Revolving Loans          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 36,249   36,249   35,268
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans     67    
Revolving Loans Converted to Term Loans          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 1,521   1,521   1,513
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans Converted to Term Loans     3    
Residential | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 2,087   2,087   3,780
Year two 3,095   3,095   1,820
Year three 1,656   1,656   1,231
Year four 1,145   1,145   4,323
Year five 4,241   4,241   3,635
Prior 13,025   13,025   9,957
Total 25,384   25,384   24,874
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Year one     0    
Year two     0    
Year three     0    
Year four     0    
Year five     0    
Prior     3    
Total     3    
Residential | Revolving Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 135   135   128
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans     0    
Residential | Revolving Loans Converted to Term Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans Converted to Term Loans     0    
Home equity lines and loans (e) | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   1
Prior 72   72   80
Total 4,891   4,891   4,807
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Year one     0    
Year two     0    
Year three     0    
Year four     0    
Year five     0    
Prior     0    
Total     3    
Home equity lines and loans (e) | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 3,445   3,445   3,363
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans     0    
Home equity lines and loans (e) | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 1,374   1,374   1,363
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans Converted to Term Loans     3    
Recreational finance | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 2,353   2,353   4,093
Year two 3,595   3,595   3,077
Year three 2,728   2,728   1,760
Year four 1,554   1,554   1,694
Year five 1,538   1,538   1,364
Prior 3,088   3,088   2,104
Total 14,856   14,856   14,092
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Year one     1    
Year two     10    
Year three     18    
Year four     16    
Year five     13    
Prior     29    
Total     87    
Recreational finance | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans     0    
Recreational finance | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans Converted to Term Loans     0    
Automobile | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 866   866   1,943
Year two 1,656   1,656   1,710
Year three 1,382   1,382   575
Year four 444   444   485
Year five 354   354   345
Prior 267   267   109
Total 4,969   4,969   5,167
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Year one     0    
Year two     6    
Year three     9    
Year four     5    
Year five     3    
Prior     2    
Total     25    
Automobile | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans     0    
Automobile | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans Converted to Term Loans     0    
Other | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 186   186   317
Year two 240   240   158
Year three 120   120   91
Year four 66   66   57
Year five 42   42   42
Prior 39   39   23
Total 2,458   2,458   2,395
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Year one     4    
Year two     9    
Year three     5    
Year four     2    
Year five     0    
Prior     0    
Total     55    
Other | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 1,763   1,763   1,705
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans     35    
Other | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 2   2   2
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]          
Revolving Loans Converted to Term Loans     0    
Current | Residential | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 2,081   2,081   3,769
Year two 3,074   3,074   1,797
Year three 1,636   1,636   1,188
Year four 1,023   1,023   4,040
Year five 3,947   3,947   3,433
Prior 11,995   11,995   9,056
Total 23,891   23,891   23,410
Current | Residential | Revolving Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 135   135   127
Current | Residential | Revolving Loans Converted to Term Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Current | Home equity lines and loans (e) | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   1
Prior 68   68   76
Total 4,781   4,781   4,690
Current | Home equity lines and loans (e) | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 3,444   3,444   3,362
Current | Home equity lines and loans (e) | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 1,269   1,269   1,251
Current | Recreational finance | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 2,349   2,349   4,081
Year two 3,580   3,580   3,052
Year three 2,702   2,702   1,729
Year four 1,527   1,527   1,673
Year five 1,516   1,516   1,345
Prior 3,038   3,038   2,066
Total 14,712   14,712   13,946
Current | Recreational finance | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Current | Recreational finance | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Current | Automobile | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 864   864   1,933
Year two 1,643   1,643   1,690
Year three 1,360   1,360   561
Year four 431   431   473
Year five 344   344   336
Prior 257   257   104
Total 4,899   4,899   5,097
Current | Automobile | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Current | Automobile | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Current | Other | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 182   182   312
Year two 237   237   155
Year three 117   117   89
Year four 65   65   56
Year five 41   41   42
Prior 39   39   22
Total 2,420   2,420   2,357
Current | Other | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 1,738   1,738   1,680
Current | Other | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 1   1   1
30-89 days past due | Residential | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 6   6   10
Year two 13   13   11
Year three 8   8   19
Year four 89   89   117
Year five 108   108   93
Prior 420   420   407
Total 644   644   657
30-89 days past due | Residential | Revolving Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
30-89 days past due | Residential | Revolving Loans Converted to Term Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
30-89 days past due | Home equity lines and loans (e) | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   0
Prior 2   2   2
Total 33   33   35
30-89 days past due | Home equity lines and loans (e) | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
30-89 days past due | Home equity lines and loans (e) | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 31   31   33
30-89 days past due | Recreational finance | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 4   4   10
Year two 11   11   20
Year three 20   20   25
Year four 18   18   17
Year five 18   18   15
Prior 40   40   29
Total 111   111   116
30-89 days past due | Recreational finance | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
30-89 days past due | Recreational finance | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
30-89 days past due | Automobile | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 2   2   8
Year two 10   10   17
Year three 19   19   13
Year four 12   12   10
Year five 9   9   7
Prior 8   8   4
Total 60   60   59
30-89 days past due | Automobile | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
30-89 days past due | Automobile | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
30-89 days past due | Other | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 2   2   3
Year two 2   2   2
Year three 2   2   1
Year four 1   1   1
Year five 1   1   0
Prior 0   0   0
Total 24   24   23
30-89 days past due | Other | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 15   15   15
30-89 days past due | Other | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 1   1   1
Accruing Loans Past Due 90 Days or More | Residential | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   1
Year two 6   6   8
Year three 8   8   21
Year four 25   25   126
Year five 139   139   90
Prior 409   409   297
Total 587   587   543
Accruing Loans Past Due 90 Days or More | Residential | Revolving Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Residential | Revolving Loans Converted to Term Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Home equity lines and loans (e) | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   0
Prior 0   0   0
Total 0   0   0
Accruing Loans Past Due 90 Days or More | Home equity lines and loans (e) | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Home equity lines and loans (e) | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Recreational finance | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   0
Prior 0   0   0
Total 0   0   0
Accruing Loans Past Due 90 Days or More | Recreational finance | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Recreational finance | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Automobile | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   0
Prior 0   0   0
Total 0   0   0
Accruing Loans Past Due 90 Days or More | Automobile | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Automobile | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Accruing Loans Past Due 90 Days or More | Other | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   0
Prior 0   0   0
Total 10   10   10
Accruing Loans Past Due 90 Days or More | Other | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 10   10   10
Accruing Loans Past Due 90 Days or More | Other | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Nonaccrual | Residential | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 2   2   4
Year three 4   4   3
Year four 8   8   40
Year five 47   47   19
Prior 201   201   197
Total 262   262   264
Nonaccrual | Residential | Revolving Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   1
Nonaccrual | Residential | Revolving Loans Converted to Term Loans | Residential real estate          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Nonaccrual | Home equity lines and loans (e) | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   0
Year two 0   0   0
Year three 0   0   0
Year four 0   0   0
Year five 0   0   0
Prior 2   2   2
Total 77   77   82
Nonaccrual | Home equity lines and loans (e) | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 1   1   1
Nonaccrual | Home equity lines and loans (e) | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 74   74   79
Nonaccrual | Recreational finance | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   2
Year two 4   4   5
Year three 6   6   6
Year four 9   9   4
Year five 4   4   4
Prior 10   10   9
Total 33   33   30
Nonaccrual | Recreational finance | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Nonaccrual | Recreational finance | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Nonaccrual | Automobile | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 0   0   2
Year two 3   3   3
Year three 3   3   1
Year four 1   1   2
Year five 1   1   2
Prior 2   2   1
Total 10   10   11
Nonaccrual | Automobile | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Nonaccrual | Automobile | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans 0   0   0
Nonaccrual | Other | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Year one 2   2   2
Year two 1   1   1
Year three 1   1   1
Year four 0   0   0
Year five 0   0   0
Prior 0   0   1
Total 4   4   5
Nonaccrual | Other | Revolving Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans 0   0   0
Nonaccrual | Other | Revolving Loans Converted to Term Loans | Consumer          
Financing Receivable, Credit Quality Indicator [Line Items]          
Revolving Loans Converted to Term Loans $ 0   $ 0   $ 0
[1] Loans of $3.1 billion and $2.1 billion at June 30, 2026 and December 31, 2025, respectively, were held in special purpose trusts to settle the respective obligations of asset-backed notes issued by those trusts. The outstanding balances of those asset-backed notes issued to third party investors were included in Long-term borrowings and were $2.8 billion at June 30, 2026 and $1.7 billion at December 31, 2025.