DERIVATIVE FINANCIAL INSTRUMENTS (Details 2) (USD $)	3 Months Ended
	Mar. 31, 2012	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 gain (loss) recognized in interest expense related to hedge ineffectiveness	848,000
Net reduction to interest expense related to net settlements of derivatives	1,500,000
Equity swap agreements
Derivative
Term of contract	5 years
Foreign exchange options
Derivative
Term of contract	5 years
Short-term Call Option | Student loans
Derivative
Total loans held for sale per call option	150,000,000
Carrying value of total loans held for sale per call option	$ 1,500,000