SEGMENT INFORMATION (Details 2) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 90,270				$ 96,663				$ 90,270	$ 96,663	$ 102,789
Sales	86,794	$ 67,211	$ 70,186	$ 67,822	86,960	$ 76,805	$ 82,356	$ 69,128	292,013	315,249	311,633
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	35,166				37,607				35,166	37,607	39,656
Sales									87,122	103,650	94,420
Other North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	0				0				0	0	0
Sales									5,546	4,820	6,474
North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	35,166				37,607				35,166	37,607	39,656
Sales									92,668	108,470	100,894
England
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	340				555				340	555	604
Sales									7,925	12,780	13,848
Germany
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	1,333				1,388				1,333	1,388	1,741
Sales									38,573	34,830	46,543
Switzerland
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	28,025				30,322				28,025	30,322	31,524
Sales									5,210	7,613	6,834
Other Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	79				74				79	74	107
Sales									39,674	42,046	35,838
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	29,777				32,339				29,777	32,339	33,976
Sales									91,382	97,269	103,063
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	9,242				10,515				9,242	10,515	11,543
Sales									94,816	92,727	88,933
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	13,534				13,453				13,534	13,453	14,603
Sales									2,957	3,772	4,296
Other Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	2,551				2,749				2,551	2,749	3,011
Sales									10,190	13,011	14,447
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 25,327				$ 26,717				25,327	26,717	29,157
Sales									$ 107,963	$ 109,510	$ 107,676