FAIR VALUE MEASUREMENTS - Assets measured at fair value on nonrecurring basis (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Level III
Assets measured at fair value on a nonrecurring basis
Mortgage servicing rights	$ 779	$ 956
Non-recurring
Assets measured at fair value on a nonrecurring basis
Impaired loans	11,057	14,362
Other real estate owned	226	239
Non-recurring | Level III
Assets measured at fair value on a nonrecurring basis
Impaired loans	11,057	14,362
Other real estate owned	$ 226	$ 239