Acquisitions - Results of Operations Since Acquisition (Details) - American Stainless Tubing, Inc. - USD ($) $ in Thousands  | 
3 Months Ended | 9 Months Ended | ||
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Sep. 30, 2020  | 
Sep. 30, 2019  | 
Sep. 30, 2020  | 
Sep. 30, 2019  | 
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| Business Acquisition [Line Items] | ||||
| Net sales | $ 8,020 | $ 8,469 | $ 22,920 | $ 26,539 | 
| Income before taxes | $ (4,233) | $ 902 | $ (2,515) | $ 2,001 | 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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