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Assets and Liabilities Held for Sale - Additional Information (Details) - USD ($) $ in Thousands |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 24, 2019 | Sep. 30, 2019 | Mar. 31, 2019
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items] |  |  |
Impairment loss |  |  | $ 6,449
Proceeds from sale of subsidiary |  | $ 602 |
Loss on sale of Energy Steel & Supply Co. |  | 87 |
Energy Steel [Member] |  |  |
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items] |  |  |
Proceeds from sale of subsidiary | $ 602 |  |
Working capital adjustment determination period | 90 days |  |
Net accounts receivable | $ 202 |  |
Loss on sale of Energy Steel & Supply Co. |  | $ 87 |

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