CONDENSED FINANCIAL STATEMENTS OF PEAPACK-GLADSTONE FINANCIAL CORPORATION (PARENT COMPANY ONLY) (STATEMENTS OF INCOME) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income
Other income									$ 73,578	$ 66,417	$ 72,243
Expenses
Interest expense	$ 43,503	$ 41,974	$ 35,931	$ 26,513	$ 16,162	$ 9,488	$ 5,627	$ 4,518	147,921	35,795	22,006
Other expenses									25,092	22,993	22,824
Total expenses	37,616	37,413	37,692	35,574	33,412	33,560	32,659	34,169
Income before income tax expense	11,623	12,600	18,108	24,950	29,510	27,749	27,293	17,792	67,281	102,344	77,662
Income tax benefit	3,024	3,845	4,963	6,595	8,931	7,623	7,193	4,351	18,427	28,098	21,040
Net income	$ 8,599	$ 8,755	$ 13,145	$ 18,355	$ 20,579	$ 20,126	$ 20,100	$ 13,441	48,854	74,246	56,622
Total comprehensive income									58,187	12,409	45,640
Parent Company [Member]
Income
Dividend from Bank									37,415	23,000
Other income									10	2
Total income									37,425	23,002
Expenses
Interest expense									6,651	5,453	7,013
Other expenses									1,481	1,130	1,602
Total expenses									8,132	6,583	8,615
Income before income tax expense									29,293	16,419	(8,615)
Income tax benefit									(2,224)	(1,676)	(2,340)
Net (loss)/income before equity in undistributed earnings of Bank									31,517	18,095	(6,275)
Equity in undistributed earnings of Bank/(dividends in excess of earnings)									17,337	56,151	62,897
Net income									48,854	74,246	56,622
Other comprehensive income/(loss)									9,333	(61,837)	(10,982)
Total comprehensive income									$ 58,187	$ 12,409	$ 45,640