Pension, Post-Retirement and Post-Employment Plans - Amounts Recognized in Balance Sheet and Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Balance Sheet
Pension and post-retirement benefits	$ 69.0	$ 73.8
Domestic | Pension Plan and SERP
Balance Sheet
Other assets	0.0	0.0
Accrued expenses and other current liabilities	1.1	0.7
Pension and post-retirement benefits	25.5	36.2
Accumulated Other Comprehensive Income (Loss) Balance Sheet
Net actuarial (loss) gain	(7.0)	(12.8)
Prior service (costs) credits	(0.1)	(0.1)
Domestic | Post-retirement Medical Benefits
Balance Sheet
Other assets	0.0	0.0
Accrued expenses and other current liabilities	0.6	0.6
Pension and post-retirement benefits	9.1	9.0
Accumulated Other Comprehensive Income (Loss) Balance Sheet
Net actuarial (loss) gain	(0.8)	(0.6)
Foreign | Pension Plan and SERP
Balance Sheet
Other assets	3.6	4.0
Accrued expenses and other current liabilities	0.7	0.6
Pension and post-retirement benefits	24.1	21.4
Accumulated Other Comprehensive Income (Loss) Balance Sheet
Net actuarial (loss) gain	(3.1)	(12.3)
Prior service (costs) credits	0.0	(0.3)
Future amortization of prior service cost (credit)	0.0
Foreign | Post-retirement Medical Benefits
Balance Sheet
Other assets	0.0	0.0
Accrued expenses and other current liabilities	0.2	0.2
Pension and post-retirement benefits	4.3	2.9
Accumulated Other Comprehensive Income (Loss) Balance Sheet
Net actuarial (loss) gain	$ (2.2)	$ (1.1)