DERIVATIVE FINANCIAL INSTRUMENTS (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2011 instrument
Derivative
Number of hedged certificates of deposit	4
Amount of each individual certificate of deposit hedged by a derivative	$ 50,000,000
Receive-fixed, Pay-variable Interest Rate Swaps
Derivative
Number of instruments entered into during the period	4
Notional amount of each individual derivative entered into during the period	50,000,000
Net loss recognized in interest expense related to hedge ineffectiveness	(891,000)
Net reduction to interest expense related to net settlements of derivatives	$ 2,500,000
Equity swap agreements
Derivative
Number of instruments entered into during the period	2
Term of contract	5 years
Foreign exchange options
Derivative
Term of contract	5 years