v3.26.1
Credit Quality and the Allowance for Loan and Lease Losses - Summary of Transactions in the ALLL by Portfolio Segment (Details) - USD ($)
$ in Millions
3 Months Ended
Feb. 01, 2026
Mar. 31, 2026
Mar. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Balance, beginning of period   $ 2,253 [1] $ 2,352
Losses charged off   (187) (173)
Recoveries of losses previously charged off   43 37
Provision for (benefit from) loan and lease losses   152 168
Adjustment for expected credit losses, PCD   180  
Allowance on PSLs at acquisition   481  
Balance, end of period   2,922 [1] 2,384
Net charge-offs (recoveries)   144 136
Comerica Incorporated      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Adjustment for expected credit losses, PCD $ 180    
Net charge-offs (recoveries)   94  
Other Consumer Loans, Point of Sale      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Losses charged off   (4) (6)
Recoveries of losses previously charged off   4 6
Commercial      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Balance, beginning of period   1,186 1,154
Losses charged off   (77) (67)
Recoveries of losses previously charged off   8 3
Provision for (benefit from) loan and lease losses   60 151
Adjustment for expected credit losses, PCD   177  
Allowance on PSLs at acquisition   466  
Balance, end of period   1,820 1,241
Residential Mortgage      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Balance, beginning of period   109 146
Losses charged off   0 0
Recoveries of losses previously charged off   0 0
Provision for (benefit from) loan and lease losses   (7) (7)
Adjustment for expected credit losses, PCD   2  
Allowance on PSLs at acquisition   4  
Balance, end of period   108 139
Consumer      
Financing Receivable, Allowance for Credit Loss [Roll Forward]      
Balance, beginning of period   958 1,052
Losses charged off   (110) (106)
Recoveries of losses previously charged off   35 34
Provision for (benefit from) loan and lease losses   99 24
Adjustment for expected credit losses, PCD   1  
Allowance on PSLs at acquisition   11  
Balance, end of period   $ 994 $ 1,004
[1] Includes $38 and $38 of other short-term investments, $463 and $554 of portfolio loans and leases, $(8) and $(9) of ALLL, $3 and $3 of other assets, $10 and $11 of other liabilities and $391 and $473 of long-term debt from consolidated VIEs that are included in their respective captions above at March 31, 2026 and December 31, 2025, respectively. For further information, refer to Note 10.