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SEGMENTS, Entity Wide Information (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 USD ($) | Sep. 30, 2017 USD ($) | Jun. 30, 2017 USD ($) | Mar. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Sep. 30, 2016 USD ($) | Jun. 30, 2016 USD ($) | Mar. 31, 2016 USD ($) | Dec. 31, 2017 USD ($) Customer | Dec. 31, 2016 USD ($) Customer | Dec. 31, 2015 USD ($) Customer
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | $ 491,611 | $ 500,153 | $ 567,080 | [1]
Long-Lived Assets | $ 71,468 |  |  |  | $ 75,109 |  |  |  | 71,468 | 75,109 |  |
Net sales to external customers | 119,940 | $ 126,386 | $ 131,617 | $ 113,668 | 118,539 | $ 128,809 | $ 131,622 | $ 121,182 | $ 491,611 | $ 500,153 | $ 567,080 | [1]
Net Sales [Member] | Customer Concentration Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of customers representing sales in excess of ten percent | Customer |  |  |  |  |  |  |  |  | 1 | 1 | 1 |
Net sales to external customers |  |  |  |  |  |  |  |  | $ 57,700 | $ 59,800 | $ 74,800 |
Concentration risk percentage |  |  |  |  |  |  |  |  | 11.70% | 12.00% | 13.20% |
Connectivity Solutions [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | $ 170,337 | $ 168,845 | $ 181,697 |
Magnetic Solutions [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 161,011 | 155,232 | 166,182 |
Power Solutions and Protection [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | $ 160,263 | 176,076 | 219,201 |
Asia [Member] | Geographic Concentration Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Concentration risk percentage |  |  |  |  |  |  |  |  | 36.90% |  |  |
United States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | $ 245,834 | 256,760 | 304,328 |
Long-Lived Assets | 27,594 |  |  |  | 29,740 |  |  |  | 27,594 | 29,740 |  |
People's Republic of China (PRC) [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Long-Lived Assets | 30,151 |  |  |  | 32,666 |  |  |  | 30,151 | 32,666 |  |
Macao [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 167,681 | 163,971 | 182,248 |
United Kingdom [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 24,110 | 21,953 | 27,552 |
Long-Lived Assets | 1,345 |  |  |  | 1,419 |  |  |  | 1,345 | 1,419 |  |
Switzerland [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 15,366 | 14,048 | 18,050 |
Long-Lived Assets | 3,632 |  |  |  | 3,593 |  |  |  | 3,632 | 3,593 |  |
Slovakia [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 14,194 | 17,622 | 2,807 |
Long-Lived Assets | 7,625 |  |  |  | 6,574 |  |  |  | 7,625 | 6,574 |  |
Germany [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 13,857 | 14,104 | 16,314 |
All Other Foreign Countries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 10,569 | 11,695 | 15,781 |
Long-Lived Assets | $ 1,121 |  |  |  | $ 1,117 |  |  |  | 1,121 | 1,117 |  |
Reportable Operating Segments [Member] | North America [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 245,834 | 256,760 | 304,328 | [1]
Net sales to external customers |  |  |  |  |  |  |  |  | 257,541 | 268,935 | 329,304 | [1]
Reportable Operating Segments [Member] | Asia [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 167,680 | 168,458 | 188,146 | [1]
Net sales to external customers |  |  |  |  |  |  |  |  | 249,506 | 256,202 | 295,751 | [1]
Reportable Operating Segments [Member] | Europe [Member] |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net sales to external customers |  |  |  |  |  |  |  |  | 78,097 | 74,935 | 74,606 | [1]
Net sales to external customers |  |  |  |  |  |  |  |  | $ 89,765 | $ 86,750 | $ 148,735 | [1]
[1] | (Revised)

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