Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 93,862	$ 67,944	$ 87,927
Foreign currency translation adjustments (Note 5)	(24,986)	(49,067)	(40,568)
Pension and post-retirement plan actuarial gains (losses), net of tax (Note 5)	1,321	6,181	(48,490)
Reclassification from accumulated other comprehensive (loss) into net income (Note 5)	3,270	0	0
Total other comprehensive loss, net of tax	(20,395)	(42,886)	(89,058)
Comprehensive income (loss)	73,467	25,058	(1,131)
Comprehensive (income) loss attributable to noncontrolling interests	(3,578)	4,280	1,176
Comprehensive income attributable to MSA Safety Incorporated	$ 69,889	$ 29,338	$ 45