Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2019 USD ($)
Accounting Policies [Abstract]
Number of reportable segments | segment									3
Allowance for doubtful accounts	$ 4.9				$ 6.2				$ 4.9	$ 6.2
Sale of accounts receivable									112.7	106.8
Expense related to discount on sale of accounts receivable									1.1	1.0
Concentration Risk [Line Items]
Net sales	379.5	$ 403.4	$ 415.3	$ 420.1	$ 405.9	$ 414.3	$ 432.2	$ 405.7	1,618.3	$ 1,658.1	$ 1,412.9
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating right-of-use assets	65.5								65.5
Operating lease assets	64.3								64.3
Accounts Receivable | Six Customers In Automotive Industry | Customer Concentration Risk
Concentration Risk [Line Items]
Uncollateralized accounts receivable	$ 44.8								$ 44.8
Percentage of concentration									17.00%
Revenue from Contract with Customer | Six Customers In Automotive Industry | Customer Concentration Risk
Concentration Risk [Line Items]
Percentage of concentration									17.00%
Net sales									$ 280.6
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating right-of-use assets												$ 69.7
Operating lease assets												$ 69.7