Income Taxes (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Income Tax Contingency [Line Items]
Effective Income Tax Rate, Continuing Operations	35.50%	35.20%
Foreign witholding taxes paid	$ 4.8	$ 16.5
Foreign Withholding Taxes Accrued			$ 2.9