INCOME TAXES - Activity related to unrecognized tax benefits, net of federal benefit, and excludes interest and penalties (Details 4) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]    
Balance at January 1 $ 25 $ 54
Decreases as a result of positions taken during prior periods (25) (29)
Balance at December 31 $ 25