Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2011	Jun. 30, 2010
Income Tax Disclosure [Abstract]
Effective income tax rate, continuing operations		23.70%	21.80%
Tax impact of patent infringement settlement	$ 11
Other tax adjustments		6.2
Additional tax expense for company's loss on future tax benefit related to Medicare Part D subsidy			$ 2.5