Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Oct. 31, 2021
Entity Listings [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 2021
Entity File Number	001-34096
Entity Registrant Name	DIME COMMUNITY BANCSHARES, INC
Entity Incorporation, State or Country Code	NY
Entity Tax Identification Number	11-2934195
Entity Address, Address Line One	898 Veterans Memorial Highway
Entity Address, City or Town	Suite 560, Hauppauge
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	11788
City Area Code	631
Local Phone Number	537-1000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		40,454,438
Entity Central Index Key	0000846617
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Stock
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, $0.01 Par Value
Trading Symbol	DCOM
Security Exchange Name	NASDAQ
Preferred stock, Series A
Entity Listings [Line Items]
Title of 12(b) Security	Preferred Stock, Series A, $0.01 Par Value
Trading Symbol	DCOMP
Security Exchange Name	NASDAQ