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Contingencies - Summary of Cumulative Trauma Product Liability Claims Activity (Detail) - LegalMatter	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Lawsuits
Loss Contingency, Quantities [Roll Forward]
Open lawsuits/Pending claims, January 1	1,794	1,988	2,326
New lawsuits/claims	398	379	340
Settled and dismissed lawsuits/claims	(772)	(573)	(678)
Open lawsuits/Pending claims, December 31	1,420	1,794	1,988
Pending claims
Loss Contingency, Quantities [Roll Forward]
Open lawsuits/Pending claims, January 1	3,023	3,779	5,539
New lawsuits/claims	455	843	465
Settled and dismissed lawsuits/claims	(1,236)	(1,599)	(2,225)
Open lawsuits/Pending claims, December 31	2,242	3,023	3,779

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The number of claims settled and dismissed during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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-Section 50
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The total number of new claims filed pertaining to a loss contingency during the period.

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