Contingencies - Summary of Cumulative Trauma Product Liability Claims Activity (Detail) - LegalMatter	6 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Loss Contingency, Quantities [Roll Forward]
Open lawsuits, beginning of period	2,326	2,840
New lawsuits	167	542
Settled and dismissed lawsuits	(446)	(1,056)
Open lawsuits, end of period	2,047	2,326

Loss Contingency, Quantities [Roll Forward]

No definition available.

Name:	msa_LossContingencyQuantitiesRollForward
Namespace Prefix:	msa_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

Name:	us-gaap_LossContingencyClaimsSettledAndDismissedNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_LossContingencyNewClaimsFiledNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

Name:	us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant