PENSION AND POSTRETIREMENT WELFARE PLANS (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Net amount recognized in the consolidated balance sheet
Accrued benefit cost at end of period	$ 3,812,000	$ 3,516,000
Changes in accrued benefit cost, prior to pension adjustments
Accrued benefit cost at end of period	3,812,000	3,516,000
Pension Plan
Pension and postretirement welfare plans
Number of last service years considered for calculating employee compensation	3 years
Change in benefit obligation:
Benefit obligation at beginning of period	5,556,000	4,629,000
Service cost	122,000	104,000
Employee contributions	9,000	11,000
Interest cost	259,000	264,000
Actuarial loss	580,000	789,000
Benefits paid	(249,000)	(241,000)
Benefit obligation at end of period	6,277,000	5,556,000
Change in plan assets:
Fair value of plan assets at beginning of period	3,418,000	3,425,000
Actual (loss) return on plan assets	469,000	(48,000)
Employee contributions	9,000	11,000
Employer contributions	439,000	271,000
Benefits and expenses paid	(249,000)	(241,000)
Fair value of plan assets at end of period	4,086,000	3,418,000
Net amount recognized in the consolidated balance sheet
Excess of projected benefit obligation over fair value of plan assets	2,191,000	2,138,000
Unrecognized loss	(2,088,000)	(1,881,000)
Accrued pension cost prior to pension adjustments	103,000	257,000
Accumulated Other Comprehensive Income at Current Measurement Date	2,088,000	1,881,000
Accrued benefit cost at end of period	2,191,000	2,138,000
Changes in accrued benefit cost, prior to pension adjustments
Accrued benefit cost at the beginning of the period	2,138,000
Net periodic postretirement cost	286,000	162,000
Employer contributions	(439,000)	(271,000)
Accrued benefit cost prior to pension adjustments	103,000	257,000
Accrued benefit cost at end of period	2,191,000	2,138,000
Accumulated benefit obligation	6,032,000	5,323,000
Amount of accumulated other comprehensive income expected to be recognized as a plan expense in 2013
Amount of accumulated other comprehensive income expected to be recognized as a plan expense	182,000
Postretirement Welfare Plan
Pension and postretirement welfare plans
Requisite service period for employees who retire after January 1, 2005 in order to be eligible for retiree medical benefits	20 years
Change in benefit obligation:
Benefit obligation at beginning of period	1,378,000	1,249,000
Service cost	22,000	22,000
Interest cost	67,000	70,000
Actuarial loss	227,000	104,000
Benefits paid, net of participant contributions	(73,000)	(67,000)
Benefit obligation at end of period	1,621,000	1,378,000
Change in plan assets:
Employer contributions	73,000	67,000
Net amount recognized in the consolidated balance sheet
Accrued pension cost prior to pension adjustments	1,333,000	2,139,000
Accrued benefit cost at end of period	1,621,000	1,378,000
Changes in accrued benefit cost, prior to pension adjustments
Accrued benefit cost at the beginning of the period	1,378,000	2,195,000
Net periodic postretirement cost	28,000	11,000
Employer contributions	(73,000)	(67,000)
Accrued benefit cost prior to pension adjustments	1,333,000	2,139,000
Required incremental (liability) asset	288,000	(761,000)
Accrued benefit cost at end of period	1,621,000	1,378,000
Amount of accumulated other comprehensive income expected to be recognized as a plan expense in 2013
Amount of accumulated other comprehensive income expected to be recognized as a plan expense	38,000
Actuarial gain	(288,000)	761,000
Postretirement Welfare Plan | Expected in 2013
Changes in accrued benefit cost, prior to pension adjustments
Required incremental (liability) asset	(26,000)
Amount of accumulated other comprehensive income expected to be recognized as a plan expense in 2013
Actuarial gain	26,000
Prior service credit	$ 12,000