Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	Apr. 30, 2019
Document Information [Line Items]
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Entity Registrant Name	Entercom Communications Corp.
Entity Central Index Key	0001067837
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Trading Symbol	ETM
Common Class A [Member]
Document Information [Line Items]
Entity Common Stock Shares Outstanding		138,563,358
Common Class B [Member]
Document Information [Line Items]
Entity Common Stock Shares Outstanding		4,045,199