v3.25.2
Document and Entity Information
Oct. 06, 2025
Document And Entity Information [Line Items]  
Entity Registrant Name COMERICA INC
Amendment Flag false
Entity Central Index Key 0000028412
Document Type 8-K
Document Period End Date Oct. 06, 2025
Entity Incorporation State Country Code DE
Entity File Number 1-10706
Entity Tax Identification Number 38-1998421
Entity Address, Address Line One Comerica Bank Tower
Entity Address, Address Line Two 1717 Main Street
Entity Address, Address Line Three MC 6404
Entity Address, City or Town Dallas
Entity Address, State or Province TX
Entity Address, Postal Zip Code 75201
City Area Code (833)
Local Phone Number 571-0486
Written Communications true
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Common Stock [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Common Stock, $5 par value
Trading Symbol CMA
Security Exchange Name NYSE
Series B Preferred Stock [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Depositary Shares, each representing a 1/40th interest in a share of 6.875% Fixed-Rate Reset Non-Cumulative Perpetual Preferred Stock, Series B
Trading Symbol CMA PrB
Security Exchange Name NYSE