Condensed Consolidated Statement of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net sales	$ 349,675	$ 339,331	$ 675,713	$ 665,225
Cost of products sold	188,591	185,495	364,647	364,050
Gross profit	161,084	153,836	311,066	301,175
Selling, general and administrative	84,009	81,962	162,437	162,213
Research and development	14,256	13,909	27,962	26,456
Restructuring charges (Note 4)	3,522	2,335	9,353	7,609
Currency exchange losses, net (Note 6)	1,290	815	18,251	2,823
Product liability expense (Note 18)	3,529	8,018	6,425	10,842
Operating income	54,478	46,797	86,638	91,232
Interest expense	4,470	5,181	6,830	9,962
Other income, net	(3,342)	(1,701)	(5,921)	(4,041)
Total other expense, net	1,128	3,480	909	5,921
Income before income taxes	53,350	43,317	85,729	85,311
Provision for income taxes (Note 10)	13,238	9,896	22,241	19,401
Net income	40,112	33,421	63,488	65,910
Net income attributable to noncontrolling interests	(306)	(242)	(450)	(360)
Net income attributable to MSA Safety Incorporated	$ 39,806	$ 33,179	$ 63,038	$ 65,550
Earnings per share attributable to MSA Safety Incorporated common shareholders:
Basic (in dollars per share)	$ 1.03	$ 0.86	$ 1.63	$ 1.71
Diluted (in dollars per share)	1.01	0.85	1.61	1.69
Dividends per common share (in dollars per share)	$ 0.42	$ 0.38	$ 0.80	$ 0.73