Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 125,115	$ 26,956	$ 93,862
Foreign currency translation adjustments (Note 5)	(30,103)	41,129	(24,986)
Pension and post-retirement plan actuarial (losses) gains, net of tax (Note 5)	(17,569)	20,120	1,321
Unrealized losses on available-for-sale securities (Note 5)	(572)	0	0
Reclassification from accumulated other comprehensive (loss) into net income (Note 5)	774	0	3,270
Total other comprehensive (loss) income, net of tax	(47,470)	61,249	(20,395)
Comprehensive income	77,645	88,205	73,467
Comprehensive income attributable to noncontrolling interests	(660)	(3,694)	(3,578)
Comprehensive income attributable to MSA Safety Incorporated	$ 76,985	$ 84,511	$ 69,889

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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