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Discontinued Operations and Related Assets Held for Sale (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2016 | Dec. 31, 2017
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract] |  |  |  |  |  |
Gain on sale of assets |  |  |  |  | $ 200 |
Discontinued Operation, Alternative Cash Flow Information [Abstract] |  |  |  |  |  |
Gain on sale of assets |  |  |  |  | 200 |
Inventories |  |  | $ (93,755) | $ 8,588 |  |
Current Liabilities: |  |  |  |  |  |
Total current liabilities of discontinued operations | $ 3,687 |  | 3,687 |  |  | $ 3,412
Engineered Solutions [Member] | Discontinued Operations, Held-for-sale [Member] |  |  |  |  |  |
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract] |  |  |  |  |  |
Net sales | 154 | $ 14,528 | 2,622 | 78,721 |  |
Cost of sales | 1,810 | 14,574 | 3,145 | 71,596 |  |
Gross (loss) profit | (1,656) | (46) | (523) | 7,125 |  |
Research and development | 0 | 106 | 0 | 1,387 |  |
Selling and administrative expenses | 64 | 3,561 | (665) | 11,360 |  |
Gain on sale of assets | (1,048) | (3,676) | (563) | (3,676) |  |
Impairment | 0 | 0 | 0 | 5,300 | 120,000 |
Operating (loss) income | (672) | (37) | 705 | (7,246) |  |
Other (income) expense |  | (56) |  | (71) |  |
other expenses | (42) |  | 24 |  |  |
Interest expense | 0 | 0 | 0 | 1,131 |  |
(Loss) income from discontinued operations before income taxes | (630) | 19 | 681 | (8,306) |  |
Provision for (benefit from) income taxes on discontinued operations | 96 | (3,215) | 96 | (3,424) |  |
Net (loss) income from discontinued operations | (726) | 3,234 | 585 | (4,882) |  |
Discontinued Operation, Alternative Cash Flow Information [Abstract] |  |  |  |  |  |
Depreciation and amortization |  |  | 0 | 2,418 |  |
Impairment | 0 | 0 | 0 | 5,300 | $ 120,000 |
Gain on sale of assets | (1,048) | $ (3,676) | (563) | (3,676) |  |
Inventories |  |  | (263) | (13,804) |  |
Deferred income taxes |  |  | 96 | (3,068) |  |
Capital expenditures |  |  | 0 | $ 528 |  |
Current Assets: |  |  |  |  |  |
Accounts receivable | 652 |  | 652 |  |  | 3,351
Inventories | 239 |  | 239 |  |  | 502
Prepaid expenses and other current assets | 6 |  | 6 |  |  | 1,137
Long-term Assets: |  |  |  |  |  |
Net property plant and equipment | 84 |  | 84 |  |  | 226
Other assets | 97 |  | 97 |  |  | 97
Total long-term assets of discontinued operations | 1,078 |  | 1,078 |  |  | 5,313
Current Liabilities: |  |  |  |  |  |
Accounts payable | 656 |  | 656 |  |  | 512
Accrued income and other taxes | 182 |  | 182 |  |  | 158
Other accrued liabilities | 2,849 |  | 2,849 |  |  | 2,742
Total current liabilities of discontinued operations | 3,687 |  | 3,687 |  |  | 3,412
Long-term Liabilities: |  |  |  |  |  |
Other long-term obligations | 636 |  | 636 |  |  | 376
Total liabilities of discontinued operations | $ 4,323 |  | $ 4,323 |  |  | $ 3,788

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