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Discontinued Operations and Related Assets Held for Sale (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 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 |  |  | $ (82,565) | $ 5,999 |  |
Current Liabilities: |  |  |  |  |  |
Total current liabilities of discontinued operations | $ 2,761 |  | 2,761 |  |  | $ 3,412
Engineered Solutions [Member] | Discontinued Operations, Held-for-sale [Member] |  |  |  |  |  |
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract] |  |  |  |  |  |
Net sales | 13 | $ 32,428 | 2,468 | 64,193 |  |
Cost of sales | 142 | 28,610 | 1,335 | 57,022 |  |
Gross (loss) profit | (129) | 3,818 | 1,133 | 7,171 |  |
Research and development | 0 | 711 | 0 | 1,281 |  |
Selling and administrative expenses | 114 | 4,106 | (244) | 7,800 |  |
Gain on sale of assets | 0 | 0 | 0 | 0 |  |
Impairment | 0 | 2,800 | 0 | 5,300 | 120,000 |
Operating (loss) income | (243) | (3,799) | 1,377 | (7,210) |  |
Other (income) expense |  | (47) |  | (18) |  |
other expenses | 72 |  | 66 |  |  |
Interest expense | 0 | 524 | 0 | 1,133 |  |
(Loss) income from discontinued operations before income taxes | (315) | (4,276) | 1,311 | (8,325) |  |
Benefit from income taxes on discontinued operations | 0 | (226) | 0 | (209) |  |
Net (loss) income from discontinued operations | (315) | (4,050) | 1,311 | (8,116) |  |
Discontinued Operation, Alternative Cash Flow Information [Abstract] |  |  |  |  |  |
Depreciation and amortization |  |  | 0 | 2,311 |  |
Impairment | 0 | 2,800 | 0 | 5,300 | $ 120,000 |
Gain on sale of assets | 0 | $ 0 | 0 | 0 |  |
Deferred income taxes |  |  | 0 | (209) |  |
Capital expenditures |  |  | 0 | $ 432 |  |
Current Assets: |  |  |  |  |  |
Accounts receivable | 1,234 |  | 1,234 |  |  | 3,351
Inventories | 191 |  | 191 |  |  | 502
Prepaid expenses and other current assets | 326 |  | 326 |  |  | 1,137
Long-term Assets: |  |  |  |  |  |
Net property plant and equipment | 0 |  | 0 |  |  | 226
Other assets | 96 |  | 96 |  |  | 97
Total long-term assets of discontinued operations | 1,847 |  | 1,847 |  |  | 5,313
Current Liabilities: |  |  |  |  |  |
Accounts payable | 905 |  | 905 |  |  | 512
Accrued income and other taxes | 181 |  | 181 |  |  | 158
Other accrued liabilities | 1,675 |  | 1,675 |  |  | 2,742
Total current liabilities of discontinued operations | 2,761 |  | 2,761 |  |  | 3,412
Long-term Liabilities: |  |  |  |  |  |
Other long-term obligations | 376 |  | 376 |  |  | 376
Total liabilities of discontinued operations | $ 3,137 |  | $ 3,137 |  |  | $ 3,788

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