CONDENSED FINANCIAL STATEMENTS OF PEAPACK-GLADSTONE FINANCIAL CORPORATION (PARENT COMPANY ONLY) (STATEMENTS OF CONDITION) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
ASSETS
Cash	$ 5,914	$ 4,415
Interest-earning deposits	154,758	108,931
Total cash and cash equivalents	160,773	113,447	$ 162,691	$ 70,160
Other assets	45,378	26,926
Total assets	4,617,858	4,260,547	3,878,633
LIABILITIES
Subordinated debt	83,193	83,024
Other liabilities	37,921	28,521
Total liabilities	4,148,845	3,856,869
SHAREHOLDERS’ EQUITY
Common stock	16,459	15,858
Surplus	309,088	283,552
Treasury stock	(8,988)	(8,988)
Retained earnings	154,799	114,468
Accumulated other comprehensive loss	(2,345)	(1,212)
Total shareholders’ equity	469,013	403,678	$ 324,210	$ 275,676
Total liabilities and shareholders’ equity	4,617,858	4,260,547
Parent Company [Member]
ASSETS
Cash	12,971	14,563
Interest-earning deposits	517	515
Total cash and cash equivalents	13,488	15,078
Investment in subsidiary	535,277	469,622
Other assets	3,734	2,551
Total assets	552,499	487,251
LIABILITIES
Subordinated debt	83,193	83,024
Other liabilities	293	549
Total liabilities	83,486	83,573
SHAREHOLDERS’ EQUITY
Common stock	16,459	15,858
Surplus	309,088	283,552
Treasury stock	(8,988)	(8,988)
Retained earnings	154,799	114,468
Accumulated other comprehensive loss	(2,345)	(1,212)
Total shareholders’ equity	469,013	403,678
Total liabilities and shareholders’ equity	$ 552,499	$ 487,251