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Business Combinations (Narrative) (Details) $ in Millions |  |  |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Aug. 08, 2017 USD ($) | Jun. 26, 2017 USD ($) | Jun. 06, 2017 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2017 Aquisition
Business Acquisition [Line Items] |  |  |  |  |
Number of acquisitions | Aquisition |  |  |  |  | 3
Santa Izabel Agro Industria, LTDA |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Acquisition price |  |  | $ 10.0 |  |
Old Dominion |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Acquisition price |  | $ 18.0 |  |  |
Net sales |  |  |  | $ 14.0 |
Net income |  |  |  | $ 0.9 |
R.P.M. |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Acquisition price | $ 13.0 |  |  |  |

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