INTANGIBLE ASSETS - Summary of carrying amount of goodwill (Details 3) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Jun. 30, 2016
Dec. 31, 2015
Sep. 30, 2015
Dec. 31, 2016
Dec. 31, 2015
Goodwill [Roll Forward]          
Beginning year       $ 43,424  
Impairment $ (7,800) $ (1,400) $ (1,300) (12,005) $ (2,712)
Ending year   43,424   33,554 43,424
Goodwill          
Goodwill [Roll Forward]          
Beginning year       43,424 44,348
Impairment       (9,870) (924)
Ending year   43,424   33,554 43,424
Trade names          
Goodwill [Roll Forward]          
Beginning year       2,972 3,632
Impairment       (2,054) (660)
Ending year   $ 2,972   $ 918 $ 2,972