SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Nature of Operations [Abstract]
Number of wholly-owned subsidiaries	4
Number of offices located In Oswego County	7
Outstanding common stock owned by the holding company (in hundredths)	60.50%
Significant Group Concentrations of Credit Risk [Abstract]
Minimum commercial real estate loans amount required for additional review	$ 400,000
Cash and Cash Equivalents [Abstract]
Maturity period for classification as cash and cash equivalents, maximum	3 months
Allowance for Loan Losses [Abstract]
Number of days past due on a non-residential consumer loan to be charged-off	120 days
Maximum percentage for estimating specific and general losses (in hundredths)	10.00%
Minimum amount, of residential mortgage loans threshold for evaluations of impairment	300,000
Minimum amount required for troubled debt restructuring	100,000
Income Recognition on Impaired and Non-accrual Loans [Abstract]
Delinquent days after which interest income is discontinued	90 days
Number of consecutive months of current payments before non-accrual troubled debt restructured loans are restored to accrual status	6 months
Derivative Financial Instruments [Abstract]
Number of interest rate swaps	1
Accumulated Other Comprehensive Loss By Component: [Abstract]
Unrealized loss for pension and other postretirement obligations	(4,608,000)	(6,029,000)	(605,000)
Tax effect	1,843,000	2,412,000	242,000
Net unrealized loss for pension and other postretirement obligations	(2,765,000)	(3,617,000)	(363,000)
Unrealized loss on financial derivative instruments used in cash flow hedging relationships	(195,000)	(200,000)	(110,000)
Tax effect	78,000	80,000	44,000
Net unrealized loss on financial derivative instruments used in cash flow hedging relationships	(117,000)	(120,000)	(66,000)
Unrealized gains on available-for-sale securities	2,606,000	1,789,000	(141,000)
Tax effect	(1,042,000)	(716,000)	56,000
Net unrealized gains on available-for-sale securities	1,564,000	1,073,000	(85,000)
Accumulated other comprehensive loss	$ (1,318,000)	$ (2,664,000)	$ (514,000)
Premises [Member] | Maximum [Member]
Premises and Equipment [Line Items]
Useful life	40 years
Equipment [Member] | Maximum [Member]
Premises and Equipment [Line Items]
Useful life	10 years