Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2011	Dec. 31, 2010
Income Tax Examination [Line Items]
Unrecognized tax benefits	$ 4.1	$ 4.5
Uncertain tax positions that would affect the effective tax rate if recognized	4.1
Offsetting reduction of a corresponding deferred tax asset	2.0
Accrued interest	0.8
Penalties	$ 0.3
Foreign Country [Member]
Income Tax Examination [Line Items]
Income tax jurisdictions outside U.S.	30