v3.25.1
Cover Page - shares
 3 Months Ended
Mar. 31, 2025
Apr. 24, 2025
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Entity File Number 001-38108  
Entity Registrant Name Cumulus Media Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 82-5134717  
Entity Address, Address Line One 780 Johnson Ferry Road NE  
Entity Address, Address Line Two Suite 500  
Entity Address, City or Town Atlanta,  
Entity Address, State or Province GA  
Entity Address, Postal Zip Code 30342  
City Area Code 404  
Local Phone Number 949-0700  
Title of 12(b) Security Class A common stock  
Trading Symbol CMLS  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Bankruptcy Proceedings, Reporting Current true  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Amendment Flag false  
CIK 0001058623  
Class A Common Stock    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   17,128,043
Class B Common Stock    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   312,041