OTHER REAL ESTATE OWNED - Summary of Activity in Purchased Other Real Estate Owned (Details) - Purchased other real estate owned - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Purchased Other Real Estate [Roll Forward]
Balance, January 1	$ 9,011	$ 12,540
Loans transferred to other real estate owned	6,396	5,023
Acquired in acquisitions	1,888	0
Portion of gains (losses) on sale and write-downs payable to (receivable from) the FDIC under loss-sharing agreements	17	86
Net gains (losses) on sale and write-downs recorded in statement of income	(690)	362
Sales proceeds	(7,087)	(9,000)
Ending balance	$ 9,535	$ 9,011