Income Taxes (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Income tax benefit in connection with stock options exercised	$ 400,000	$ 223,000	$ 237,000
Unrecognized tax benefits that would impact effective tax rate	23,900,000	23,200,000
Short-term reserves	3,700,000
Long-term reserves	30,700,000
Total amount of accrued interest and penalties unrecognized tax benefits	4,500,000	3,900,000
Unrecognized tax benefits, income tax penalties and interest expense recognized	600,000	(700,000)	(1,500,000)
Gross unrecognized tax benefits change range, minimum	0
Gross unrecognized tax benefits change range, maximum	3,700,000
Net operating loss carry forwards, for state income tax purposes	91,500,000
Foreign subsidiary earnings	142,900,000
Amount of earnings to be repatriated from foreign subsidiaries upon asset divestiture	$ 44,100,000