v3.26.1
Cover Page Document
Aug. 11, 2026
Jun. 09, 2026
Cover [Abstract]    
Entity Incorporation, State or Country Code DE  
Document Type 8-K  
Document Period End Date Aug. 11, 2026  
Entity Registrant Name CME GROUP INC.  
Entity Tax Identification Number 36-4459170  
Entity Address, Street Address 20 South Wacker Drive  
Entity Address, City or Town Chicago  
Entity Address, State or Province IL  
Entity Address, Postal Zip Code 60606  
City Area Code 312  
Local Phone Number 930-1000  
Written Communications false  
Soliciting Material false  
Pre-commencement Tender Offer false  
Pre-commencement Tender Offer false  
Title of 12(b) Security Class A Common Stock  
Trading Symbol CME  
Security Exchange Name NASDAQ  
Entity Emerging Growth Company false  
Entity Central Index Key 0001156375 0001156375
Amendment Flag false false
Entity File Number 001-31553