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Investment in Joint Venture - Additional Information (Detail) - USD ($) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2018 | Sep. 30, 2017
Joint Venture |  |
Schedule of Equity Method Investments [Line Items] |  |
Net sales |  | $ 0.2
Joint Venture | Maximum |  |
Schedule of Equity Method Investments [Line Items] |  |
Net sales | $ 0.2 |
Wuxi Weifu Autocam Precision Machinery Company, Ltd. |  |
Schedule of Equity Method Investments [Line Items] |  |
Investment in joint venture | 49.00% |

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- Definition Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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