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SEGMENTS (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 USD ($) | Jun. 30, 2017 USD ($) | Jun. 30, 2018 USD ($) Industry Segment | Jun. 30, 2017 USD ($)
SEGMENTS [Abstract] |  |  |  |
Number of industry in which entity operates | Industry |  |  | 1 |
Number of reportable operating segments | Segment |  |  | 3 |
Summary of key financial data [Abstract] |  |  |  |
Net sales | $ 140,710 | $ 131,617 | $ 258,961 | $ 245,285
Income from operations | 10,667 | 7,266 | 11,104 | 9,621
North America [Member] |  |  |  |
Summary of key financial data [Abstract] |  |  |  |
Net sales | 71,240 | 64,905 | 130,696 | 125,335
Asia [Member] |  |  |  |
Summary of key financial data [Abstract] |  |  |  |
Net sales | 45,914 | 46,071 | 84,535 | 81,883
Europe [Member] |  |  |  |
Summary of key financial data [Abstract] |  |  |  |
Net sales | 23,556 | 20,641 | 43,730 | 38,067
Reportable Operating Segments [Member] | North America [Member] |  |  |  |
Summary of key financial data [Abstract] |  |  |  |
Net sales | 74,602 | 67,970 | 137,173 | 131,125
Income from operations | 2,963 | 1,210 | 2,661 | 2,202
Reportable Operating Segments [Member] | Asia [Member] |  |  |  |
Summary of key financial data [Abstract] |  |  |  |
Net sales | 70,005 | 70,419 | 126,144 | 126,830
Income from operations | 5,319 | 5,314 | 5,234 | 6,350
Reportable Operating Segments [Member] | Europe [Member] |  |  |  |
Summary of key financial data [Abstract] |  |  |  |
Net sales | 27,630 | 23,416 | 51,942 | 43,801
Income from operations | 2,385 | 742 | 3,209 | 1,069
Intersegment Elimination [Member] |  |  |  |
Summary of key financial data [Abstract] |  |  |  |
Net sales | $ (31,527) | $ (30,188) | $ (56,298) | $ (56,471)

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