Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Definite-Lived Intangible Assets [Roll Forward]
Beginning Balance		$ 61.0
Additions		2.8
Amortization		(5.6)	$ (5.5)	$ (5.2)
Ending Balance		58.2	61.0
Definite-Lived Intangible Assets, Estimated Annual Amortization Expense [Abstract]
2019		5.3
2020		4.9
2021		4.9
2022		4.6
2023		4.3
Thereafter		34.2
Intangible Assets [Abstract]
Total Intangible Assets		74.8	77.6
Total Intangible Assets, Additions		2.8
Total Intangible Assets, Amortization		(5.6)	(5.5)	$ (5.2)
Accumulated Amortization		$ 20.4	14.8
Weighted Average [Member]
Definite-Lived Intangible Assets [Roll Forward]
Useful Life (Years)		6 years
Trademarks and Trade Names [Member]
Indefinite-Lived Intangible Assets [Roll Forward]
Beginning Balance		$ 16.6
Additions		0.0
Ending Balance		16.6	16.6
Customer Relationships [Member]
Definite-Lived Intangible Assets [Roll Forward]
Beginning Balance		54.7
Additions		0.2
Amortization		(4.2)
Ending Balance		$ 50.7	54.7
Useful Life (Years)		19 years
Intangible Assets [Abstract]
Total Intangible Assets, Amortization		$ (4.2)
Developed Technology and Other [Member]
Definite-Lived Intangible Assets [Roll Forward]
Beginning Balance	[1]	6.3
Additions	[1]	2.6
Amortization	[1]	(1.4)
Ending Balance	[1]	7.5	$ 6.3
Intangible Assets [Abstract]
Total Intangible Assets, Amortization	[1]	$ (1.4)
Developed Technology and Other [Member] | Minimum [Member]
Definite-Lived Intangible Assets [Roll Forward]
Useful Life (Years)		4 years
Developed Technology and Other [Member] | Maximum [Member]
Definite-Lived Intangible Assets [Roll Forward]
Useful Life (Years)		10 years
Developed Technology and Other [Member] | Weighted Average [Member]
Definite-Lived Intangible Assets [Roll Forward]
Useful Life (Years)		17 years

[1] Developed Technology and Other includes patents, non-compete agreements, land easements and trade names with finite lives.