BUSINESS SEGMENTS - Schedule of Income and Total Assets for Reportable Segments (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Net interest income		$ 39,622	$ 31,793
Noninterest income		14,714	17,820
Total income		54,336	49,613
Provision for credit losses	[1]	2,375	225
Compensation and employee benefits		22,449	21,990
Premises and equipment		4,647	4,113
FDIC insurance expense		471	585
Other operating expense		6,602	4,906
Total operating expense		36,544	31,819
INCOME BEFORE INCOME TAX EXPENSE		17,792	17,794
Income tax expense		4,351	4,616
NET INCOME		13,441	13,178
Total assets at period end		6,255,664	5,969,627	$ 6,077,993
Banking Segment [Member]
Net interest income		37,999	30,226
Noninterest income		(429)	5,140
Total income		37,570	35,366
Provision for credit losses		2,375	225
Compensation and employee benefits		16,403	16,428
Premises and equipment		3,931	3,570
FDIC insurance expense		471	585
Other operating expense		4,166	2,391
Total operating expense		27,346	23,199
INCOME BEFORE INCOME TAX EXPENSE		10,224	12,167
Income tax expense		2,300	3,159
NET INCOME		7,924	9,008
Total assets at period end		6,155,011	5,883,553
Peapack Private Segment [Member]
Net interest income		1,623	1,567
Noninterest income		15,143	12,680
Total income		16,766	14,247
Provision for credit losses		0	0
Compensation and employee benefits		6,046	5,562
Premises and equipment		716	543
FDIC insurance expense		0	0
Other operating expense		2,436	2,515
Total operating expense		9,198	8,620
INCOME BEFORE INCOME TAX EXPENSE		7,568	5,627
Income tax expense		2,051	1,457
NET INCOME		5,517	4,170
Total assets at period end		$ 100,653	$ 86,074

[1] Commencing on January 1, 2022, the allowance calculation is based on the current expected credit loss methodology.  Prior to January 1, 2022, the calculation was based on the incurred loss methodology.