Condensed Consolidated Balance Sheet (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Current assets
Cash and cash equivalents	$ 58,822	$ 59,760
Trade receivables, less allowance for doubtful accounts of $7,625 and $9,391	204,675	198,551
Inventories	157,299	150,581
Deferred tax assets	25,918	25,714
Income taxes receivable	3,734	12,936
Prepaid expenses and other current assets	30,664	29,847
Total current assets	481,112	477,389
Property, less accumulated depreciation of $322,520 and $316,288	154,465	156,789
Prepaid pension cost	129,768	121,631
Deferred tax assets	7,436	8,285
Goodwill	262,283	263,089
Other noncurrent assets	188,109	170,005
Total assets	1,223,173	1,197,188
Current liabilities
Notes payable and current portion of long-term debt	8,523	10,163
Accounts payable	53,511	58,460
Employees' compensation	40,228	36,845
Insurance and product liability	20,059	18,401
Taxes on income	4,509	1,253
Other current liabilities	50,544	56,619
Total current liabilities	177,374	181,741
Long-term debt	377,063	367,094
Pensions and other employee benefits	127,821	126,479
Deferred tax liabilities	48,574	49,177
Other noncurrent liabilities	17,320	16,647
Total liabilities	748,152	741,138
Mine Safety Appliances Company shareholders' equity:
Common stock - authorized 180,000,000 shares of no par value; issued 62,081,391 and 62,081,391 shares (outstanding 36,643,634 and 36,519,726 shares)	94,628	88,629
Stock compensation trust - 1,215,769 and 1,360,714 shares	(6,346)	(7,103)
Treasury shares, at cost:
Accumulated other comprehensive loss	(55,023)	(44,316)
Retained earnings	700,858	676,195
Total Mine Safety Appliances Company shareholders' equity	471,454	451,368
Noncontrolling interests	3,567	4,682
Total shareholders' equity	475,021	456,050
Total liabilities and equity	1,223,173	1,197,188
Preferred Stock, 4 1/ 2% Cumulative [Member]
Mine Safety Appliances Company shareholders' equity:
Preferred stock	3,569	3,569
Treasury shares, at cost:
Treasury shares, at cost	(1,753)	(1,753)
Second Cumulative Preferred Voting Stock [Member]
Mine Safety Appliances Company shareholders' equity:
Preferred stock
Common Stock [Member]
Treasury shares, at cost:
Treasury shares, at cost	$ (264,479)	$ (263,853)