Other Expense Restructuring and Related Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Payments to acquire property, plant, and equipment			$ 74.7	$ 101.3
Severance charges	$ 0.1	$ 0.0	3.4	0.0
Other charges	0.7	0.0	2.5	0.0
Restructuring and related charges	1.2		6.7
Restructuring Reserve [Roll Forward]
Charges	1.2	$ 0.0	6.7	$ 0.0
Asset-related charges [Member]
Restructuring Reserve [Roll Forward]
Cash payments			0.0
Other charges [Member]
Restructuring Reserve [Roll Forward]
Cash payments			0.0
2018 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Severance charges	0.1		3.4
Asset impairment charges, patent and equipment	0.4		0.8
Other charges	0.7		2.5
Restructuring and related charges	1.2		6.7
Restructuring Reserve [Roll Forward]
Balance, December 31, 2017			0.0		$ 0.0
Charges			6.7
Cash payments			(0.2)
Non-cash asset-write-downs			(3.3)
Balance, September 30, 2018	3.2		3.2
2018 Restructuring Plan [Member] | Severance and benefits [Member]
Restructuring Reserve [Roll Forward]
Balance, December 31, 2017			0.0		0.0
Charges			3.4
Cash payments			(0.2)
Non-cash asset-write-downs			0.0
Balance, September 30, 2018	3.2		3.2
2018 Restructuring Plan [Member] | Asset-related charges [Member]
Restructuring Reserve [Roll Forward]
Balance, December 31, 2017			0.0		0.0
Charges			0.8
Non-cash asset-write-downs			(0.8)
Balance, September 30, 2018	0.0		0.0
2018 Restructuring Plan [Member] | Other charges [Member]
Restructuring Reserve [Roll Forward]
Balance, December 31, 2017			0.0		0.0
Charges			2.5
Non-cash asset-write-downs			(2.5)
Balance, September 30, 2018	0.0		0.0
2018 Restructuring Plan [Member] | Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost					8.0
Payments to acquire property, plant, and equipment					9.0
Effect on future earnings					17.0
2018 Restructuring Plan [Member] | Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost					13.0
Payments to acquire property, plant, and equipment					14.0
Effect on future earnings					$ 22.0
2016 Restructuring Plan [Member]
Restructuring Reserve [Roll Forward]
Balance, September 30, 2018	$ 1.0		$ 1.0