Consolidated Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 87,927us-gaap_ProfitLoss	$ 88,049us-gaap_ProfitLoss	$ 91,761us-gaap_ProfitLoss
Foreign currency translation adjustments	(40,568)	(7,281)	3,846
Pension and post-retirement plan actuarial (losses) and gains	(48,490)	54,951	(28,018)
Comprehensive (loss) income	(1,131)	135,719	67,589
Comprehensive loss (income) attributable to noncontrolling interests	1,176	1,331	(840)
Comprehensive income attributable to MSA Safety Incorporated	$ 45us-gaap_ComprehensiveIncomeNetOfTax	$ 137,050us-gaap_ComprehensiveIncomeNetOfTax	$ 66,749us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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