Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Tax Contingency [Line Items]
Deferred tax assets, valuation allowance	$ 40.1	$ 38.9
Deferred tax assets, tax loss carryforwards	53.0	41.3
Operating loss carryforwards	66.1
Excess of financial reporting over the tax basis in investments	734
Unrecognized tax benefits that would impact effective tax rate	54.3	58.3	71.3
Unrecognized tax benefit that would result in adjustments to deferred taxes	4.5	7.8	8.1
Unrecognized tax benefits, income tax penalties expense	(1.1)	0.6	3.5
Unrecognized tax benefits, interest on income taxes expense	0.7	(3.7)	5.3
Recognized liabilities for penalties	6.5	7.8	6.0
Recognized liabilities for expense	11.4	10.9	14.4
Significant change in unrecognized tax benefits is reasonably possible, amount of unrecorded benefit	10
Taxing Jurisdictions [Member]
Income Tax Contingency [Line Items]
Deferred tax assets, tax loss carryforwards	19.0
Foreign Country [Member]
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 113.0