Income Taxes - Schedule of Liabilities for Income Tax (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Tax Disclosure [Abstract]
Deferred Income Tax Liabilities	$ 15.1	$ 0
Unrecognized Tax Benefits	6.4	6.2	7.8	11.7
Liabilities for Income Taxes	$ 21.5	$ 6.2