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Discontinued Operations and Related Assets Held for Sale - Narratives (Details) - USD ($) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Jul. 03, 2017 | Nov. 30, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Cash received from divestitures |  |  | $ 0 | $ 27,254 | $ 15,889
Discontinued Operations, Held-for-sale [Member] | Engineered Solutions [Member] |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Impairment |  |  | $ 0 | 5,300 | 119,907
Cash received from divestitures |  |  |  | $ 27,254 | $ 15,889
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Fiber Materials Inc. |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Cash received from divestitures |  | $ 15,900 |  |  |
Loss on sale of business |  | 200 |  |  |
Potential Proceeds from Business Divested |  | $ 8,500 |  |  |
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member] | Advanced Energy Technologies [Member] |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Cash received from divestitures | $ 28,500 |  |  |  |

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