Document and Entity Information (USD $) In Millions, except Share data	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Entity Registrant Name	CUMULUS MEDIA INC
Entity Central Index Key	0001058623
Document Type	10-Q
Document Period End Date	Jun. 30, 2011
Amendment Flag	false
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Entity Public Float		$ 49.5
Entity Common Stock, Shares Outstanding	52,505,196
Common Class A
Entity Common Stock, Shares Outstanding	39,420,658
Common Class B
Entity Common Stock, Shares Outstanding	5,809,191
Common Class C
Entity Common Stock, Shares Outstanding	644,871
Common Class D
Entity Common Stock, Shares Outstanding	6,630,476