SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2012
Weighted average assumptions used to determine the benefit obligation and net benefit cost
Discount rate, to determine the benefit obligation (as a percent)	3.90%				3.90%
Average rate of increase in compensation, to determine the benefit obligation (as a percent)	3.00%				3.00%
Discount rate, to determine net benefit cost (as a percent)					3.90%
Average rate of increase in compensation, to determine net benefit cost (as a percent)					3.00%
Change in Benefit Obligation
Net benefit cost accrued at the beginning of the period	$ 20,125	$ 20,230	$ 17,433	$ 17,510	$ 20,230
Service cost	230	230	247	247
Interest cost	190	190	202	202
Payments	(180)	(525)		(526)
Net benefit cost accrued at the end of the period	$ 20,365	$ 20,125	$ 17,882	$ 17,433	$ 20,365