VARIABLE INTEREST ENTITIES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Cash and cash equivalents	$ 211,834	$ 221,038	$ 173,857	$ 153,210
Premises and equipment, net	119,988	123,393
Other assets	223,498	249,488
Variable Interest Entity, Primary Beneficiary [Member] | 706 North Clinton [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Cash and cash equivalents	104	74
Premises and equipment, net	6,109	6,266
Other assets	33	5
Total assets	6,246	6,345
Total liabilities	0	$ 0
Minority interest	3,100
Loss of minority interest	4,800
Minority interest loss exposure related to financing agreement	$ 1,700
Variable Interest Entity, Primary Beneficiary [Member] | 706 North Clinton [Member] | Oneida Preferred Funding II LLC [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Percentage of membership interest	50.00%