Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	May 10, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	DIME COMMUNITY BANCSHARES INC
Entity Central Index Key	0001005409
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Ex Transition Period	false
Entity Common Stock, Shares Outstanding		36,056,385
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1