SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Product Warranty (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Accrual at beginning of the year	$ 2,622	$ 3,084
Provision	3,076	1,958
Settlement and Other	(2,558)	(2,420)
Accrual at end of year	$ 3,140	$ 2,622