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COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) Subsidiary
Future minimum lease payments for operating leases [Abstract] |  |  |
2018 | $ 5,819 |  |
2019 | 4,194 |  |
2020 | 3,717 |  |
2021 | 3,112 |  |
2022 | 1,357 |  |
Thereafter | 448 |  |
Total future minimum lease payments for operating leases | 18,647 |  |
Rent expense for leases | 8,200 | $ 7,900 | $ 8,800
Other commitments [Abstract] |  |  |
Outstanding purchase orders related to raw materials | 45,400 | 31,000 |
Outstanding purchase orders related to capital expenditures | 3,000 | $ 2,800 |
Arezzo Revenue Agency [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Noncurrent liability and offsetting indemnification asset | $ 12,000 |  |
Setec [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Number of subsidiaries named in the lawsuit | Subsidiary |  |  | 3

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