Commitments and Contingencies (Details 2) (USD $)	12 Months Ended
Dec. 31, 2014 ClassActions
Commercial Litigation - Ceradyne Inc.
Loss contingencies
Number of purported class actions filed	4
Commercial Litigation - Ceradyne Inc. California Superior Court
Loss contingencies
Number of purported class actions filed	2
Commercial Litigation - Ceradyne Inc. Delaware Chancery Court
Loss contingencies
Number of purported class actions filed	2
Commercial Litigation - TransWeb Corporation
Loss contingencies
Number of counts jury did not rule in favor of Transweb	1
Number of 3M patents unenforceable due to inequitable conduct	2
Potential maximum loss exposure due to judgment against 3M	26,000,000
Accrued loss contingency reserve	0

The total number of purported class actions filed pertaining to a loss contingency during the period.

No definition available.

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- Definition

Number of counts jury did not rule in favor of Transweb.

+ References

No definition available.

+ Details

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- Definition

The number of 3M patents that the court found to be unenforceable due to inequitable conduct.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of loss contingency liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

+ Details

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- Definition

The estimated maximum amount of possible loss from the contingency.

+ 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 (b)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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- Details

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- Details

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