Employee Benefit Plans - Components of Net Periodic Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Settlement charge			$ 0.0	$ 1.2
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 0.3	$ 0.3	0.9	0.9
Expected return on plan assets	(0.3)	(0.4)	(0.7)	(1.4)
Amortization of net actuarial loss	0.2	0.1	0.6	0.5
Settlement charge	0.0	1.2	0.0	1.2
Net periodic benefit cost	$ 0.2	$ 1.2	$ 0.8	$ 1.2