Cover page - shares	9 Months Ended
	Sep. 30, 2019	Oct. 31, 2019
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Entity Registrant Name	Entercom Communications Corp.
Entity Central Index Key	0001067837
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Security 12 b Title	Class A Common Stock, par value $.01 per share
Trading Symbol	ETM
Security Exchange Name	NYSE
Entity File Number	001-14461
Entity Incorporation State Country Code	PA
Entity TaxIdentification Number	23-1701044
EntityAddressAddressLine1	2400 Market Street
EntityAddressAddressLine2	4th Floor
EntityAddressCityOrTown	Philadelphia
EntityAddressStateOrProvince	PA
Entity Address Postal Zip Code	19103
City Area Code	(610)
Local Phone Number	660-5610
Document Quarterly Report	true
Document Transition Report	false
Common Class A [Member]
Document Information [Line Items]
Entity Common Stock Shares Outstanding		133,583,583
Common Class B [Member
Document Information [Line Items]
Entity Common Stock Shares Outstanding		4,045,199