Condensed Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 23,376	$ 32,489
Other comprehensive income, net of tax:
Foreign currency translation adjustments (Note 6)	361	13,400
Pension and post-retirement plan actuarial gains, net of tax (Note 6)	2,023	2,329
Unrealized gains on available-for-sale securities (Note 6)	536	0
Reclassification of currency translation from accumulated other comprehensive (loss) into net income (Note 6)	15,359	0
Total other comprehensive income, net of tax	18,279	15,729
Comprehensive income	41,655	48,218
Comprehensive income attributable to noncontrolling interests	(287)	(288)
Comprehensive income attributable to MSA Safety Incorporated	$ 41,368	$ 47,930

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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