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INCOME TAXES, Uncertain Tax Positions and Interest and Penalties (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Income Tax Contingency [Line Items] |  |  |  |
Liabilities for uncertain tax positions current | $ 2,500 | $ 400 |  |
Liability for uncertain tax positions noncurrent | 27,948 | 27,458 |  |
Liability for uncertain positions expected to be resolved in next fiscal year | 2,500 |  |  |
Interest and penalties uncertain tax positions recognized | 900 | 1,300 | $ 2,500 |
Reconciliation of beginning and ending amount of liability for uncertain tax positions [Roll Forward] |  |  |  |
Liability for uncertain tax positions - beginning of period | 27,828 | 42,158 | 39,970 |
Additions based on tax positions related to the current year | 2,168 | 2,483 | 3,241 |
Translation adjustment - increase | 804 |  |  |
Translation adjustment - decrease |  | (881) | (844) |
Settlement/expiration of statutes of limitations | (370) | (15,932) | (209) |
Liability for uncertain tax positions - end of period | 30,430 | 27,828 | 42,158 | $ 39,970
Interest and Penalties [Abstract] |  |  |  |
Benefit on reversal of interest and penalties | 0 | (3,100) |  |
Accrued interest and penalties uncertain tax positions | 3,200 | 2,200 |  |
Maximum [Member] |  |  |  |
Interest and Penalties [Abstract] |  |  |  |
Benefit on reversal of interest and penalties |  |  | $ (100) |
Tax Year 2014 [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Liabilities for uncertain tax positions current | 1,400 |  |  |
Tax Year 2006 [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Liabilities for uncertain tax positions current | 1,100 |  |  |
Power Solutions [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Reduction relating to settlement with taxing authorities | (13,900) |  |  |
Reduction relating to interest and penalties uncertain tax positions | (11,100) |  |  |
Interest and penalties uncertain tax positions recognized | $ 5,300 |  |  |
Interest and penalties uncertain tax positions recognized reversal |  | 2,600 |  |
Reconciliation of beginning and ending amount of liability for uncertain tax positions [Roll Forward] |  |  |  |
Additions relating to acquisitions |  |  |  | $ 12,000
Interest and Penalties [Abstract] |  |  |  |
Interest and penalties uncertain tax positions recognized until various tax matters are resolved |  | $ 2,100 |  |
Asia [Member] | Power Solutions [Member] | Minimum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Income tax audit, years under examination | 2004 |  |  |
Asia [Member] | Power Solutions [Member] | Maximum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Income tax audit, years under examination | 2006 |  |  |

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