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Other Expense - Additional Information (Detail) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Jun. 24, 2019 | Mar. 31, 2020 | Dec. 31, 2019
Other Expenses [Line Items] |  |  |
Proceeds from sale of subsidiary |  |  | $ 602
Loss on sale of Energy Steel & Supply Co. |  |  | $ 87
Westinghouse Electric Company [Member] |  |  |
Other Expenses [Line Items] |  |  |
Bad debt charge |  | $ 98 |
Inventory write down |  | 338 |
Energy Steel [Member] |  |  |
Other Expenses [Line Items] |  |  |
Proceeds from sale of subsidiary | $ 602 |  |
Loss on sale of Energy Steel & Supply Co. |  | $ 87 |

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- Definition Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116847112&loc=d3e4542-108314 + Details
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