Quarterly Financial Information (Unaudited) - Schedule of Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 443,254	$ 381,694	$ 372,313	$ 330,692	$ 410,268	$ 340,197	$ 341,289	$ 308,428	$ 1,527,953	$ 1,400,182	$ 1,348,223
Gross profit	197,252	169,395	164,400	142,784	178,124	149,439	153,000	134,785	673,831	615,348	595,492
Net income attributable to MSA Safety Incorporated	$ 51,489	$ 44,906	$ 47,693	$ 35,542	$ (61,476)	$ 21,180	$ 25,186	$ 36,450	$ 179,630	$ 21,340	$ 124,077
Earnings per share
Basic (in dollars per share)	$ 1.31	$ 1.15	$ 1.21	$ 0.90	$ (1.57)	$ 0.54	$ 0.64	$ 0.93	$ 4.58	$ 0.54	$ 3.19
Diluted (in dollars per share)	$ 1.31	$ 1.14	$ 1.21	$ 0.90	$ (1.57)	$ 0.54	$ 0.64	$ 0.92	$ 4.56	$ 0.54	$ 3.15