Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Jul. 31, 2020
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	01-14461
Entity Registrant Name	Entercom Communications Corp.
Entity Incorporation, State or Country Code	PA
Entity Tax Identification Number	23-1701044
Entity Address, Address Line One	2400 Market Street
Entity Address, Address Line Two	4th Floor
Entity Address, City or Town	Philadelphia
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19103
City Area Code	(610)
Local Phone Number	660-5610
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Title of 12(b) Security	Class A Common Stock, par value $.01 per share
Trading Symbol	ETM
Security Exchange Name	NYSE
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001067837
Current Fiscal Year End Date	--12-31
Common Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		133,959,300
Common Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		4,045,199