Retirement and Other Postretirement Benefit Plans - Schedule of Net Periodic Benefit Costs of Defined Benefit Retirement Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
U.S. Non-qualified Defined Benefit Retirement Plans
Net periodic benefit costs of defined benefit retirement plans
Service cost	$ 0.3	$ 0.3
Interest cost	0.1	0.2
Net amortization and deferral	0.8	0.9
Settlement expense		1.3
Net periodic benefit cost (credit)	1.2	2.7
European Defined Benefit Retirement Plans
Net periodic benefit costs of defined benefit retirement plans
Service cost	0.2	0.2
Interest cost	1.6	1.8
Expected return on plan assets	(2.2)	(2.4)
Net amortization and deferral	0.2	0.1
Net periodic benefit cost (credit)	$ (0.2)	$ (0.3)