Income Taxes - Income Tax Reconciliation (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Tax at statutory U.S. tax rate	$ (8.1)	$ (113.2)	$ (10.6)
State income taxes, net of federal benefit	(0.2)	(6.3)	(1.9)
Net effect of international operations	3.1	25.0	(0.8)
Settlement of UK pension plan	(2.3)	0	0
Valuation allowances	(3.2)	89.2	11.6
U.S. tax on foreign earnings	6.2	3.9	4.8
Stock-based compensation	3.1	2.4	1.6
Uncertain tax positions	2.2	0.3	0.2
Other	0.6	0.1	0.1
Income tax provision	$ 1.4	$ 1.4	$ 5.0