Condensed Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 36,406	$ 40,112	$ 80,209	$ 63,488
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments (Note 6)	4,669	(385)	(18,278)	(24)
Pension and post-retirement plan actuarial gains, net of tax (Note 6)	3,090	1,378	6,192	3,401
Unrealized gain on available-for-sale securities (Note 6)	124	27	62	563
Reclassification of currency translation from accumulated other comprehensive (loss) into net income (Note 6)	0	0	720	15,359
Total other comprehensive income (loss), net of tax	7,883	1,020	(11,304)	19,299
Comprehensive income	44,289	41,132	68,905	82,787
Comprehensive income attributable to noncontrolling interests	(358)	(169)	(371)	(456)
Comprehensive income attributable to MSA Safety Incorporated	$ 43,931	$ 40,963	$ 68,534	$ 82,331

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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