Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2011 Person	Dec. 31, 2010	Dec. 31, 2009
Detailed information about the allowance for doubtful accounts
Allowance for doubtful accounts	$ 10,443,000	$ 11,156,000	$ 10,685,000
Bad debt expense	2,349,000	2,935,000	2,676,000
Major customer details disclosure
Number of customers representing greater than 10% of net sales or accounts receivable	0
Percentage of net sales or accounts receivable to be considered a major customer	10.00%
Research and development expenses
Expenditures for company-sponsored research and development activities	30,400,000	27,300,000	28,300,000
Income taxes payable included in accrued expenses and other current liabilities		8,800,000
Non-current deferred tax liabilities included in other non-current liabilities		$ 2,200,000
Buildings [Member]
Estimated useful lives of the assets
Property, plant and equipment, useful lives, maximum	40
Property, plant and equipment, useful lives, minimum	20
Machinery and equipment [Member]
Estimated useful lives of the assets
Property, plant and equipment, useful lives, maximum	15
Property, plant and equipment, useful lives, minimum	5
Software [Member]
Estimated useful lives of the assets
Property, plant and equipment, useful lives, maximum	12
Property, plant and equipment, useful lives, minimum	1