COMMITMENTS, CONTINGENCIES AND DERIVATIVES (Schedule of customer loan swaps) (Details) $ in Thousands		Sep. 30, 2018 USD ($) derivative	Dec. 31, 2017 USD ($) derivative
Derivative [Line Items]
Derivative, Number of Instruments Held | derivative		2
Derivative, fair value		$ 241	$ 142
Interest rate swaps
Derivative [Line Items]
Notional amount of derivative		43,000	43,000
Derivative, fair value	[1]	$ 4,361	$ 7,571
Interest rate swaps | Federal home loan bank 30-day
Derivative [Line Items]
Derivative, Number of Instruments Held | derivative		8	23
Notional amount of derivative		$ 56,720	$ 124,784
Derivative, fair value		684	1,799
Forward-Starting Interest Rate Swap
Derivative [Line Items]
Notional amount of derivative		25,000	50,000
Derivative, fair value	[2]	$ 65	$ 21
Commercial and Industrial Sector [Member] | Interest rate swaps
Derivative [Line Items]
Derivative, Number of Instruments Held | derivative		75	65
Notional amount of derivative		$ 396,606	$ 351,668
Derivative, fair value		$ 14,878	$ 3,237
Loans [Member] | Interest rate swaps
Derivative [Line Items]
Derivative, Number of Instruments Held | derivative		150	130
Notional amount of derivative		$ 793,212	$ 703,336
Derivative, fair value		$ 0	$ 0
Other Liabilities [Member] | Interest rate swaps | Federal home loan bank 30-day
Derivative [Line Items]
Derivative, Number of Instruments Held | derivative		67	42
Notional amount of derivative		$ 339,886	$ 226,884
Derivative, fair value		$ (15,562)	$ (5,036)

[1] Presented within accrued interest and other liabilities on the consolidated statements of condition.

[2] Presented within accrued interest and other liabilities on the consolidated statements of condition.