Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Loss that will be amortized from accumulated other comprehensive income in the next year	$ 3.9
Prior service cost that will be amortized from accumulated other comprehensive income in the next year	$ 0.2
Unrecognized net gains and losses from all sources, threshold	10.00%
Estimated future benefit payments 2018	$ 21.5
Estimated future benefit payments 2019	18.2
Estimated future benefit payments 2020	18.9
Estimated future benefit payments 2021	18.9
Estimated future benefit payments 2022	18.4
Estimated future benefit payments, from 2023 to 2026	89.8
Net defined contribution plan expense recognized	12.1	$ 11.5	$ 12.0
Minimum
Defined Benefit Plan Disclosure [Line Items]
Estimated future benefit payments 2018	$ 10.7
Two Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Plan assets concentration	15.00%	30.00%
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 150.0	$ 150.8
Lump sum payment	0.0	19.3
Pre-tax non-cash settlement loss	$ 0.0	$ 7.4	0.0
Fixed-income investments, expected real rate of return	2.00%
Long-term rate of inflation	3.00%
Discount rate used to determine net postretirement benefit expense	3.50%
U.S. Plans | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation assumption to equity investments	65.00%
Equity investment, actual asset allocation	76.00%	64.00%
U.S. Plans | Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation assumption to equity investments	35.00%
Equity investments, expected real rate of return	6.00%
Equity investment, actual asset allocation	24.00%	36.00%
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 140.2	$ 123.3
Lump sum payment	0.0	0.0
Pre-tax non-cash settlement loss	$ 0.0	$ 0.0	$ 0.9
Discount rate used to determine net postretirement benefit expense	2.30%
Non-U.S. Plans | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation assumption to equity investments	50.00%
Actual asset allocation of other investments	48.00%
Non-U.S. Plans | Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation assumption to equity investments	50.00%
Actual asset allocation of other investments	52.00%