Condensed Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 14,690	$ 12,073
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments (Note 6)	10,744	13,948
Pension and post-retirement plan adjustments, net of tax (Note 6)	1,984	1,892
Total other comprehensive income, net of tax	12,728	15,840
Comprehensive income	27,418	27,913
Comprehensive loss attributable to noncontrolling interests	349	2
Comprehensive income attributable to MSA Safety Incorporated	$ 27,767	$ 27,915

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, 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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