Interim Financial Statements - Additional Information (Detail) $ in Millions	6 Months Ended
Jun. 30, 2017 USD ($) Segment ManufacturingPlants
Interim Reporting [Line Items]
Number of manufacturing plants \| ManufacturingPlants	40
Number of reportable segments \| Segment	3
Wuxi Weifu Autocam Precision Machinery Company, Ltd. [Member]
Interim Reporting [Line Items]
Investment in joint venture	49.00%
ASU 2016-09 [Member]
Interim Reporting [Line Items]
Reclassification of tax benefits from deferred taxes to retained earnings \| $	$ 0.7

Interim Reporting [Line Items]

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- Definition

Number of manufacturing plants.

+ References

No definition available.

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- Definition

Amount of the cumulative effect on retained earnings net of related income tax effect.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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