Income Taxes (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Net deferred tax liability	$ 2.5	$ 0.1
Income tax receivable	27.3	9.6
Income tax refunds	16.5
Net operating loss carryforwards	617.2
Estimated amount of net operating loss carryforwards that will not be utilized	99.0
Foreign tax credit carryforwards, subject to expriration	15.3
Valuation allowance	448.4	336.6
Unrecognized tax benefits that would impact effective tax rate	25.8	23.9
Unrecognized Tax Benefits, Interest on Income Taxes Expense	2.2	1.5
Interest accrual reversal	5.6
Interest accrued net reduction	3.4
Total amount of interest accrued for uncertain tax positions	15.7	19.1
Tax paid for settlement of IRS audit	3.3
Interest paid for settlement of IRS audit	2.2
Amount by which unrecognized tax benefits may decrease over the next 12 months	$ 18.0