INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current [Abstract]
Federal									$ 4,989	$ 4,178	$ 5,208
State and local									515	694	223
Total current tax									5,504	4,872	5,431
Deferred [Abstract]
Federal									2,343	1,139	(885)
State and local									28	429	(747)
Total deferred tax									2,371	1,568	(1,632)
Valuation allowance									(253)	(554)	(79)
Total	$ 1,369	$ 2,118	$ 2,159	$ 1,976	$ 1,202	$ 1,864	$ 1,579	$ 1,241	$ 7,622	$ 5,886	$ 3,720
Effective income tax rate reconciliation [Abstract]
Federal income tax expense at statutory rates									35.00%	35.00%	35.00%
Surtax exemption									(1.00%)	(1.00%)	(1.00%)
Tax-exempt income									(8.00%)	(10.00%)	(14.00%)
State and local income taxes, net of federal benefit									2.00%	2.00%	1.00%
Deferred tax asset adjustment and change in rate									0.00%	(1.00%)	(2.00%)
Other									0.00%	0.00%	1.00%
Total									28.00%	25.00%	20.00%
Deferred tax assets [Abstract]
Allowance for loan losses	8,244				8,392				$ 8,244	$ 8,392	$ 7,576
Deferred compensation	1,560				1,624				1,560	1,624	1,652
Stock-based compensation	763				640				763	640	459
Realized losses on securities reclassed from available for sale to held to maturity	49				930				49	930	1,180
Unfunded pension obligation	3,277				2,529				3,277	2,529	2,496
Alternative minimum tax credit	0				2,427				0	2,427	3,925
Net operating loss carryforward	699				614				699	614	1,169
Other	1,170				1,104				1,170	1,104	992
Total deferred tax assets	15,762				18,260				15,762	18,260	19,449
Deferred tax liabilities [Abstract]
Unrealized gains on securities available for sale	(71)				(957)				(71)	(957)	(1,724)
Other	(608)				(844)				(608)	(844)	(842)
Total deferred tax liabilities	(679)				(1,801)				(679)	(1,801)	(2,566)
Valuation allowance	(699)				(614)				(699)	(614)	(1,169)
Net deferred tax assets	14,384				15,845				14,384	15,845	15,714
Income Tax Contingency [Line Items]
Valuation allowance	699				614				699	614	1,169
Unrecognized tax benefits including interest	0				$ 0				0	$ 0	$ 34
New York State [Member]
Deferred tax liabilities [Abstract]
Valuation allowance	(699)								(699)
Income Tax Contingency [Line Items]
Net operating loss carryforwards	14,400								14,400
Valuation allowance	$ 699								$ 699
Operating loss carryforwards, expiration date									Dec. 31, 2032