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SEGMENTS, Entity Wide Information (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) Customer | Dec. 31, 2017 USD ($) Customer
Segment Information by Geographic Area [Abstract] |  |
Net sales | $ 548,184 | $ 491,611
Long-lived assets | 70,013 | 71,468
Net Sales [Member] | Customer Concentration Risk [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | $ 67,700 | $ 57,700
Number of customers representing sales in excess of ten percent | Customer | 1 | 1
Concentration risk percentage | 12.30% | 11.70%
Connectivity Solutions [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | $ 186,724 | $ 170,337
Magnetic Solutions [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 185,407 | 161,011
Power Solutions and Protection [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 176,053 | 160,263
United States [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 271,691 | 245,834
Long-lived assets | 27,505 | 27,594
Macao [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 187,204 | 167,681
United Kingdom [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 26,340 | 24,110
Long-lived assets | 2,330 | 1,345
Slovakia [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 24,123 | 14,194
Long-lived assets | 6,475 | 7,625
Germany [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 15,298 | 13,857
Switzerland [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 13,279 | 15,366
Long-lived assets | 3,023 | 3,632
All Other Foreign Countries [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 10,249 | 10,569
Long-lived assets | 1,117 | 1,121
Asia [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | $ 187,203 | 167,680
Asia [Member] | Assets [Member] | Geographic Concentration Risk [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Concentration risk percentage | 41.30% |
Asia [Member] | Connectivity Solutions [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | $ 17,140 |
Asia [Member] | Magnetic Solutions [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 137,998 |
Asia [Member] | Power Solutions and Protection [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Net sales | 32,065 |
People's Republic of China (PRC) [Member] |  |
Segment Information by Geographic Area [Abstract] |  |
Long-lived assets | $ 29,563 | $ 30,151

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