MARKETABLE SECURITIES - Sale of Securities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Sale of Marketable Securities [Abstract]
Proceeds	$ 9,457	$ 14,762	$ 9,457	$ 14,762
Gross gains	0	38	0	38
Gross losses	$ (51)	(13)	(51)	(13)
Held-to-maturity Securities, Sales, Excluding Other than Temporary Impairments [Abstract]
Proceeds from sales		923	$ 0	923
Amortized cost		907		907
Gross realized gains		16		16
Tax expense related to securities gains/losses		$ (4)		$ (4)