Income Taxes (Details7) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions	$ 1.3	$ 1.5	$ 1.2
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued	5.7	0.6
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Unrecognized Tax Benefits	29.7	17.1	37.3	34.7
Increases in prior period tax positions	1.3	1.5	1.2
Business Acquisition, Preacquisition Contingency, Amount	14.5
Decreases in prior period tax positions	(1.3)	(15.8)	0
Increases in current period tax positions	0.1	0.3	0.7
Decreases in current period tax positions	0	0	(0.8)
Unrecognized Tax Benefits Increases Resulting From Settlements With Taxing Authorities	0.7
Unrecognized Tax Benefits, Reductions Resulting from Lapse of Applicable Statute of Limitations	1.8
Decreases from settlements with taxing authorities		(1.1)	0
Interest and penalties, net	(0.5)	(5.1)	(1.5)
Unrecognized Tax Benefits Period Increase Decrease		18.5
Unrecognized Tax Benefits Interest And Penalties Period Change Due To Settlements		5.7
Unrecognized Tax Benefits Income Tax Penalties And Interest Expense	0.5	5.1	1.5
Deferred Tax Changes Due To Settlements Of Uncertain Tax Positions		12.8
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued	5.7	0.6
Other		1.8
Unrecognized Tax Benefits That Would Impact Effective Tax Rate	23.0
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible Amount Of Unrecorded Benefit	3.0
Series of Individually Immaterial Business Acquisitions [Member]
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions	14.5
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued	2.5
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Increases in prior period tax positions	14.5
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued	$ 2.5