RETIREMENT FUND AND PROFIT SHARING PLAN (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Employer match of the first 1% of compensation contributed by participants (in hundredths)	100.00%
Percentage of participant contribution under condition one (in hundredths)	1.00%
Employer match of the next 5% compensation contributed by participants (in hundredths)	50.00%
Percentage of employee deferrals under condition two (in hundredth)	5.00%
Balance sheet amounts [Abstract]
Minimum pension obligation and unfunded pension liability	$ 11,462,000		$ 11,045,000
SERP [Member]
Components of SERP expense [Abstract]
Service cost	139,000	109,000
Interest cost	112,000	104,000
Amortization of adjustments	77,000	58,000
Total SERP expense	328,000	271,000
Balance sheet amounts [Abstract]
Minimum pension obligation and unfunded pension liability	11,462,000		11,045,000
Amounts recognized in accumulated other comprehensive loss, pretax [Abstract]
Prior service cost	1,005,000		877,000
Net gains	2,844,000		2,884,000
Total amounts recognized in accumulated other comprehensive loss	3,849,000		3,761,000
401(k) Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Compensation expense	100,000	100,000
401(k) Plan [Member] | Class A [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares owned by plan (in shares)	15,325
401(k) Plan [Member] | Class B [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares owned by plan (in shares)	216,867
Non-defined Retirement Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Compensation expense	$ 100,000	$ 100,000
Non-defined Retirement Fund [Member] | Class A [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares owned by plan (in shares)	3,323
Non-defined Retirement Fund [Member] | Class B [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares owned by plan (in shares)	17,342