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INCOME TAXES, Uncertain Tax Positions and Interest and Penalties (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Income Taxes Uncertain Tax Positions and Tax Reform [Abstract] |  |
Liabilities for uncertain tax positions - current | $ 1,400 | $ 2,500
Liability for uncertain tax positions - noncurrent | 27,553 | 27,948
Liability for uncertain positions expected to be resolved in next fiscal year | 1,100 |
Interest and penalties uncertain tax positions recognized | 1,300 | 900
Reconciliation of beginning and ending amount of liability for uncertain tax positions [Roll Forward] |  |
Liability for uncertain tax positions - beginning of period | 30,430 | 27,828
Additions based on tax positions related to the current year | 1,703 | 2,168
Additions relating to acquisitions | 0 | 0
Translation adjustment - increase |  | 804
Translation adjustment - decrease | (657) |
Settlement/expiration of statutes of limitations | (2,525) | (370)
Liability for uncertain tax positions - end of period | 28,951 | 30,430
Interest and Penalties [Abstract] |  |
(Benefit) on reversal of interest and penalties | (300) | 0
Accrued interest and penalties uncertain tax positions | 3,800 | 3,200
Tax Year 2008 [Member] |  |
Income Taxes Uncertain Tax Positions and Tax Reform [Abstract] |  |
Liabilities for uncertain tax positions - current | 1,000 |
Tax Year 2006 [Member] |  |
Income Taxes Uncertain Tax Positions and Tax Reform [Abstract] |  |
Liabilities for uncertain tax positions - current |  | 1,100
Tax Year 2014 [Member] |  |
Income Taxes Uncertain Tax Positions and Tax Reform [Abstract] |  |
Liabilities for uncertain tax positions - current |  | $ 1,400
Tax Year 2015 [Member] |  |
Income Taxes Uncertain Tax Positions and Tax Reform [Abstract] |  |
Liabilities for uncertain tax positions - current | $ 100 |

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