Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Line Items]
Amended prior period tax returns		1.40%	18.30%	2.30%
Percentage increase in uncertain tax position			0.60%
Uncertain tax positions			$ 1.0
Percentage decrease from uncertain tax positions			5.90%
Decrease from uncertain tax positions			$ 9.9
Tax benefits on certain foreign investments		(2.00%)	(0.70%)	(17.00%)
Differences in rates of foreign operations				$ (15.0)
Permanent tax differences		0.30%	1.80%	(2.10%)
Permanent tax differences amount				$ (1.9)
Changes in valuation allowances		0.40%	0.30%	7.80%
Changes in valuation allowances				$ 6.9
Foreign tax credit carryforwards		$ 23.0	$ 37.4
Gross state net operating loss carryforwards		173.2
Foreign subsidiaries gross net operating loss carryforwards		85.2
Undistributed earnings of non-United States subsidiaries		336.9
Income tax payments		50.3	57.7	70.0
Income tax refunds		2.4	2.6	4.2
Income from continuing operations, before income taxes		222.3	167.7	88.4
Income tax penalties and interest accrued		3.3	$ 4.5
Income tax expense if unrecognized tax benefits were recognized		5.8
Foreign Subsidiaries
Income Taxes [Line Items]
Percentage increase in uncertain tax position			4.70%
Uncertain tax positions			$ 7.9
Domestic and Foreign Tax Authority
Income Taxes [Line Items]
Increase (decrease) in valuation allowance		17.5
Other net deferred tax assets
Income Taxes [Line Items]
Increase (decrease) in valuation allowance		$ 2.3
Domestic Tax Authority
Income Taxes [Line Items]
Income from continuing operations, before income taxes				$ 9.7
Tax Year 2004-2012 [Member]
Income Taxes [Line Items]
Amended prior period tax returns			18.30%
Foreign tax credit			$ 30.7
Scenario, Forecast
Income Taxes [Line Items]
Reduction in unrecognized tax benefits on the outcome of tax examinations and the expiration of statutes of limitations	$ 0.7