Summary of Cumulative Trauma Product Liability Claims Activity (Detail)	6 Months Ended	12 Months Ended
Jun. 30, 2013 LegalMatter	Dec. 31, 2012 LegalMatter
Commitments and Contingencies Disclosure [Abstract]
Open claims, beginning of period	2,609	2,321
New claims	268	750
Settled and dismissed claims	(161)	(462)
Open claims, end of period	2,716	2,609

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The number of claims settled and dismissed during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

+ Details

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- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

+ Details

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- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

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