Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 01, 2019
Document And Entity Information [Abstract]
Entity Registrant Name	PEAPACK GLADSTONE FINANCIAL CORP
Entity Central Index Key	0001050743
Document Type	10-Q
Document Period End Date	Jun. 30, 2019
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		19,456,312
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2019
Trading Symbol	PGC
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-16197
Entity Tax Identification Number	223537895
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	New Jersey
Entity Address, Postal Zip Code	07921-0700
City Area Code	908
Local Phone Number	234-0700