Condensed Consolidated Statement Of Income (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidated Statement Of Income [Abstract]
Net sales	$ 298,241	$ 242,019	$ 869,473	$ 691,626
Other income, net	2,398	1,039	4,353	2,359
Total revenues	300,639	243,058	873,826	693,985
Costs and expenses
Cost of products sold	177,353	151,340	519,179	428,268
Selling, general and administrative	78,621	61,185	227,382	184,005
Research and development	9,663	7,938	29,646	23,956
Restructuring and other charges	1,004	2,082	6,118	11,509
Interest	3,198	1,686	10,423	4,911
Currency exchange losses (gains)	431	3,545	986	(90)
Total costs and expenses	270,270	227,776	793,734	652,559
Income before income taxes	30,369	15,282	80,092	41,426
Provision for income taxes	10,188	5,297	26,934	14,387
Net income	20,181	9,985	53,158	27,039
Net income attributable to noncontrolling interests	(209)	(382)	(285)	(703)
Net income attributable to Mine Safety Appliances Company	$ 19,972	$ 9,603	$ 52,873	$ 26,336
Earnings per share attributable to Mine Safety Appliances Company common shareholders
Basic	$ 0.54	$ 0.27	$ 1.44	$ 0.73
Diluted	$ 0.54	$ 0.26	$ 1.42	$ 0.72
Dividends per common share	$ 0.26	$ 0.25	$ 0.77	$ 0.74