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REVENUE, Disaggregation of Revenue (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | $ 140,710 | $ 131,617 | $ 258,961 | $ 245,285
Direct to Customer [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 99,447 |  | 184,464 |
Through Distribution [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 41,263 |  | 74,497 |
Connectivity Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 48,928 |  | 91,846 |
Magnetic Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 45,548 |  | 83,776 |
Power Solutions and Protection [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 46,234 |  | 83,339 |
North America [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 71,240 | 64,905 | 130,696 | 125,335
North America [Member] | Direct to Customer [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 44,055 |  | 81,951 |
North America [Member] | Through Distribution [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 27,185 |  | 48,745 |
North America [Member] | Connectivity Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 34,834 |  | 65,878 |
North America [Member] | Magnetic Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 10,158 |  | 18,209 |
North America [Member] | Power Solutions and Protection [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 26,248 |  | 46,609 |
Asia [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 45,914 | 46,071 | 84,535 | 81,883
Asia [Member] | Direct to Customer [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 39,402 |  | 72,330 |
Asia [Member] | Through Distribution [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 6,512 |  | 12,205 |
Asia [Member] | Connectivity Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 4,820 |  | 8,241 |
Asia [Member] | Magnetic Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 32,844 |  | 60,669 |
Asia [Member] | Power Solutions and Protection [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 8,250 |  | 15,625 |
Europe [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 23,556 | $ 20,641 | 43,730 | $ 38,067
Europe [Member] | Direct to Customer [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 15,990 |  | 30,183 |
Europe [Member] | Through Distribution [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 7,566 |  | 13,547 |
Europe [Member] | Connectivity Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 9,274 |  | 17,727 |
Europe [Member] | Magnetic Solutions [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | 2,546 |  | 4,898 |
Europe [Member] | Power Solutions and Protection [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Disaggregation of revenue | $ 11,736 |  | $ 21,105 |

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