Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2023	Nov. 01, 2023
Cover [Abstract]
Entity Registrant Name	PEAPACK-GLADSTONE FINANCIAL CORPORATION
Entity Central Index Key	0001050743
Document Type	10-Q
Document Period End Date	Sep. 30, 2023
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		17,818,529
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2023
Trading Symbol	PGC
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-16197
Entity Tax Identification Number	22-3537895
Entity Address, Address Line One	500 Hills Drive
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Bedminster
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07921-0700
City Area Code	908
Local Phone Number	234-0700
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	NJ
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, no par value
Security Exchange Name	NASDAQ