Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
Tax Credit Carryforward [Line Items]
Unrecognized tax benefits affecting effective tax rate	$ 48.7
Interest and penalties associated with unrecognized tax benefits (Operations)	0.9
Interest and penalties associated with unrecognized tax benefits (Balance Sheet)	25.3
State and Local Jurisdiction [Member]
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards	365.0
Deferred tax assets, operating loss and tax credit carryforwards	27.8
Net operating loss carryforwards, valuation allowance	4.8
Foreign Tax Authority [Member]
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards	14.2
Operating loss carryforwards, valuation allowance	20.7
Wisconsin Research And Development Credit [Member] | State and Local Jurisdiction [Member] | Wisconsin [Member]
Tax Credit Carryforward [Line Items]
Net capital loss carryforwards	$ 13.7