Reclassifications out of Accumulated Other Comprehensive Loss (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit [Roll Forward]
Total other comprehensive (loss) income	$ (48,490)	$ 54,951	$ (28,018)
MSA Safety Incorporated
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit [Roll Forward]
Balance at beginning of period	(77,080)	(132,031)	(104,013)
Unrecognized net actuarial (losses) gains	(84,495)	72,008	(45,793)
Unrecognized prior service credit	302	239	0
Tax benefit (expense)	29,832	(25,783)	13,833
Total other comprehensive (loss) income before reclassifications, net of tax	(54,361)	46,464	(31,960)
Amortization of prior service cost	(251)	(322)	(353)
Recognized net actuarial losses	9,114	13,875	6,764
Tax benefit	(2,992)	(5,066)	(2,469)
Total amount reclassified from accumulated other comprehensive loss, net of tax	5,871	8,487	3,942
Total other comprehensive (loss) income	(48,490)	54,951	(28,018)
Balance at end of period	(125,570)	(77,080)	(132,031)
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translations [Roll Forward]
Balance at beginning of period	(1,189)	4,959	829
Foreign currency translation adjustments, parent	(39,971)	(6,148)	4,130
Balance at end of period	(41,160)	(1,189)	4,959
Noncontrolling Interests
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translations [Roll Forward]
Balance at beginning of period	(1,602)	(469)	(185)
Foreign currency translation adjustments, noncontrolling interest	(597)	(1,133)	(284)
Balance at end of period	$ (2,199)	$ (1,602)	$ (469)

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The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Amount before tax of cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to noncontrolling interests.

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Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount after tax, before reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount before tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss related to net period benefit cost (credit) for pension and other postretirement defined benefit plans.

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Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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