Income Taxes (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Loss Carryforwards [Line Items]
Equity Method Investment, Summarized Financial Information, Income Tax		$ 15.2	$ 9.2
Effective Income Tax Rate Reconciliation, Percent	32.70%	41.20%	18.20%
Cumulative amount of undistributed earning of foreign subsidiaries	727.7
Alternative minimum tax credit	9.2	8.4
Foreign tax credit	3.6	3.6
Foreign tax credits valuation allowance	3.6	3.6
State net operating loss	28.7	27.1
State net operating loss carryforwards valuation allowance	11.3	11.2
Foreign net operating loss	5.8	8.5
Unrecognized Tax Benefits	5.6	5.7	4.7
Decrease in income tax expenses unrecognized tax benefits if recognized	3.6	3.9
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	0.3	1.0
Reductions due to expiration of the applicable statute of limitations	0.4	0
Effective Income Tax Rate Reconciliation, Tax Contingency, Domestic, Amount	(0.2)	0.6	(15.5)
Tax On Gain Of Affiliate Sale	0	(23.2)	0
Domestic [Member]
Operating Loss Carryforwards [Line Items]
Amount of U.S. federal tax net operating loss	119.3
Foreign [Member]
Operating Loss Carryforwards [Line Items]
Equity Method Investment, Summarized Financial Information, Income Tax		7.6	4.6
Amount of U.S. federal tax net operating loss	$ 5.6