MORTGAGE SERVICING RIGHTS - Balance of loans serviced for others and fair value of mortgage servicing rights (Details) (Balance of loans serviced for others and fair value of mortgage servicing rights, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Balance of loans serviced for others and fair value of mortgage servicing rights
Residential mortgage loans serviced for others	$ 138,106	$ 146,258
Fair value of mortgage servicing rights	$ 1,568	$ 1,579