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Discontinued Operations and Related Assets Held for Sale (Details) - USD ($) $ in Thousands | 5 Months Ended | 6 Months Ended | 7 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 31, 2015 | Jun. 30, 2018 | Jun. 30, 2017 | Aug. 14, 2015 | Dec. 31, 2017 | Dec. 31, 2016
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 | $ 47,853 | $ (82,565) | $ 5,999 |  | $ (15,649) | 53,548
Current Liabilities: |  |  |  |  |  |
Total current liabilities of discontinued operations |  | 2,761 |  |  | 3,412 | 20,042
Engineered Solutions [Member] | Discontinued Operations, Held-for-sale [Member] |  |  |  |  |  |
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract] |  |  |  |  |  |
Net sales | 55,608 | 2,468 | 64,193 | $ 98,024 | 82,299 | 115,336
Cost of sales | 49,068 | 1,335 | 57,022 | 94,817 | 74,723 | 98,440
Gross (loss) profit | 6,540 | 1,133 | 7,171 | 3,207 | 7,576 | 16,896
Research and development |  | 0 | 1,281 |  |  |
Selling and administrative expenses | 8,627 | (244) | 7,800 | 16,764 | 12,239 | 19,220
Gain on sale of assets |  | 0 | 0 |  | (6,091) | 198
Impairment |  | 0 | 5,300 |  | 5,300 | 120,000
Operating (loss) income | (4,143) | 1,377 | (7,210) | (20,228) | (5,266) | (124,971)
Other (income) expense | (135) |  | (18) | (90) | (115) | (66)
other expenses |  | 66 |  |  |  |
Interest expense | 918 | 0 | 1,133 | 907 | 1,133 | 3,258
(Loss) income from discontinued operations before income taxes | (4,926) | 1,311 | (8,325) | (21,045) | (6,284) | (128,163)
Benefit from income taxes on discontinued operations |  | 0 | (209) | (2,366) | (55) | (1,189)
Net (loss) income from discontinued operations | (4,926) | 1,311 | (8,116) | $ (18,679) | (6,229) | (126,974)
Discontinued Operation, Alternative Cash Flow Information [Abstract] |  |  |  |  |  |
Depreciation and amortization | 4,194 | 0 | 2,311 |  | 2,418 | 5,277
Impairment |  | 0 | 5,300 |  | 5,300 | 120,000
Gain on sale of assets |  | 0 | 0 |  | (6,091) | 198
Inventories | 3,514 |  |  |  | 15,217 | (917)
Deferred income taxes |  | 0 | (209) |  | (55) | (1,189)
Capital expenditures | $ 4,447 | 0 | $ 432 |  | 558 | 4,713
Current Assets: |  |  |  |  |  |
Accounts receivable |  | 1,234 |  |  | 3,351 | 17,094
Inventories |  | 191 |  |  | 502 | 71,816
Prepaid expenses and other current assets |  | 326 |  |  | 1,137 | 320
Long-term Assets: |  |  |  |  |  |
Net property plant and equipment |  | 0 |  |  | 226 | 79,048
Other assets |  | 96 |  |  | 97 | 12,608
Total long-term assets of discontinued operations |  | 1,847 |  |  | 5,313 | 180,886
Current Liabilities: |  |  |  |  |  |
Accounts payable |  | 905 |  |  | 512 | 7,253
Accrued income and other taxes |  | 181 |  |  | 158 |
Other accrued liabilities |  | 1,675 |  |  | 2,742 | 10,463
Total current liabilities of discontinued operations |  | 2,761 |  |  | 3,412 | 20,042
Long-term Liabilities: |  |  |  |  |  |
Other long-term obligations |  | 376 |  |  | 376 | 850
Total liabilities of discontinued operations |  | $ 3,137 |  |  | $ 3,788 | $ 20,892

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