PENSION, OTHER POST RETIREMENT BENEFIT AND PROFIT SHARING PLANS (Details) (USD $)	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Pension Benefits [Member]
Change in benefit obligations:
Projected benefit obligations at beginning of year	$ 156,595,000		$ 134,892,000		$ 120,050,000
Service cost	8,107,000		7,449,000		7,127,000
Interest cost	8,327,000		7,676,000		7,019,000
Amendments	(8,494,000)		0		330,000
Actuarial loss	22,253,000		11,457,000		4,882,000
Benefits paid	(4,197,000)		(4,879,000)		(4,516,000)
Administrative expenses paid	(229,000)		0		0
Projected benefit obligations at end of year	182,362,000		156,595,000		134,892,000
Change in plans assets:
Fair value of plans assets at beginning of year	197,536,000		180,217,000		116,136,000
Actual return on assets	1,347,000		21,488,000		29,740,000
Employer contributions	547,000		710,000		38,857,000
Benefits paid	(4,197,000)		(4,879,000)		(4,516,000)
Administrative expenses paid	(229,000)		0		0
Fair value of plans assets at end of year	195,004,000		197,536,000		180,217,000
Funded status:
Projected benefit obligations	(182,362,000)		(156,595,000)		(134,892,000)
Fair value of plans assets	195,004,000		197,536,000		180,217,000
Unrecognized transition amount	0		0		0
Unrecognized prior service cost	0		0		0
Unrecognized actuarial loss	0		0		0
Net amount recognized	12,642,000		40,941,000		45,325,000
Amounts recognized in the consolidated balance sheets consisted of:
Prepaid benefit cost	102,307,000		104,749,000		105,900,000
Accrued benefit liability	(20,572,000)		(18,678,000)		(16,868,000)
Intangible asset	0		0		0
Accumulated other comprehensive income adjustment	(69,093,000)		(45,130,000)		(43,707,000)
Net amount recognized	12,642,000		40,941,000		45,325,000
Pre-tax amounts recognized in accumulated other comprehensive income consisted of:
Net transition obligation	55,000		73,000
Net prior service (benefit) cost	(6,901,000)		1,623,000
Net actuarial loss	75,939,000		43,434,000
Total accumulated other comprehensive income	69,093,000		45,130,000		43,707,000
Net transition obligation that will be amortized into net periodic cost over the next fiscal year	18,000
Net prior service credit that will be amortized into net periodic cost over the next fiscal year	768,000
Net actuarial loss that will be amortized into net periodic cost over the next fiscal year	5,725,000
Components of net periodic benefit cost:
Service cost	8,107,000		7,449,000		7,127,000
Interest cost	8,327,000		7,676,000		7,019,000
Expected return on assets	(14,864,000)		(14,032,000)		(10,698,000)
Amortization of unrecognized transition amount	18,000		18,000		18,000
Recognized prior service cost	31,000		341,000		342,000
Recognized net loss	3,264,000		2,218,000		4,320,000
Net periodic benefit cost	4,883,000		3,670,000		8,128,000
Information related to the Company's defined benefit pension plans [Abstract]
Accumulated benefit obligation	172,439,000		140,967,000
Basic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
General information	The Basic Plan is a non-contributory defined benefit pension plan managed by a trustee covering substantially all full-time employees who have at least one year of service, have attained the age of 21 and were hired prior to January 1, 2006. During 2011, the Basic Plan was amended to implement a 2.5 cash balance formula that becomes effective January 1, 2012 for employees hired on or after January 1, 2006. Prior to this amendment, benefits were based on years of service and the employee's compensation.
Weighted-average assumptions used to determine benefit obligation [Abstract]
Discount rate (in hundredths)	4.80%		5.50%
Rate of compensation increase (in hundredths)	2.00%	[1]	2.50%	[1]
Rate of compensation increase used for next fiscal year (in hundredths)			3.00%
Rate of compensation increase used for year two and beyond (in hundredths)			3.00%
Weighted-average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate (in hundredths)	5.50%		6.00%		6.25%
Rate of compensation increase (in hundredths)	3.00%		3.00%		3.60%
Expected rate of return on plan assets (in hundredths)	8.00%		8.00%		8.00%
Restoration Plan and Supplemental Plan [Member]
Accumulated benefit obligations in excess of plan assets [Abstract]
Projected benefit obligation	26,712,000		23,468,000
Accumulated benefit obligation	25,409,000		22,439,000
Fair value of assets	$ 0		$ 0
Restoration Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
General information	The Restoration Plan provides for the payment of retirement benefits to certain participants in the Basic Plan.
Weighted-average assumptions used to determine benefit obligation [Abstract]
Discount rate (in hundredths)	4.45%		5.15%
Rate of compensation increase (in hundredths)	2.00%	[1]	2.50%	[1]
Rate of compensation increase used for next fiscal year (in hundredths)			3.00%
Rate of compensation increase used for year two and beyond (in hundredths)			3.00%
Weighted-average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate (in hundredths)	5.15%		5.85%		6.50%
Rate of compensation increase (in hundredths)	3.00%		3.00%		3.60%
Supplemental Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
General information	The Supplemental Plan is a non-qualified defined benefit supplemental retirement plan for certain key employees. Benefits commence when the employee retires and are payable over a period of ten years.
Weighted-average assumptions used to determine benefit obligation [Abstract]
Discount rate (in hundredths)	3.85%		4.50%
Rate of compensation increase (in hundredths)	2.00%	[1]	2.50%	[1]
Rate of compensation increase used for next fiscal year (in hundredths)			3.00%
Rate of compensation increase used for year two and beyond (in hundredths)			3.00%
Weighted-average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate (in hundredths)	4.50%		5.35%		6.50%
Rate of compensation increase (in hundredths)	3.00%		3.00%		3.60%

[1] 3.00% rate of compensation increase used for 2012 and beyond.