Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2022	Apr. 10, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K/A
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	000-17820
Entity Registrant Name	LAKELAND BANCORP, INC
Entity Incorporation, State or Country Code	NJ
Entity Tax Identification Number	22-2953275
Entity Address, Address Line One	250 Oak Ridge Road
Entity Address, City or Town	Oak Ridge
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07438
City Area Code	973
Local Phone Number	697-2000
Title of 12(b) Security	Common Stock, no par value
Trading Symbol	LBAI
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 901,705,000
Entity Common Stock, Shares Outstanding (in shares)		65,018,978
Documents Incorporated by Reference	None
Amendment Flag	false
Entity Central Index Key	0000846901
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY