Other Expense Restructuring and Related Charges (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Payments to acquire property, plant, and equipment	$ 28.8	$ 28.0
Severance charges	0.3	2.0
Other charges	0.3	1.2
Restructuring and related charges	0.6	3.3
Restructuring Reserve [Roll Forward]
Charges	0.6	3.3
Non-cash asset-write-downs	(0.3)	(0.1)
Severance and benefits [Member]
Restructuring Reserve [Roll Forward]
Balance, December 31, 2018	2.3
Charges	0.3
Cash payments	(1.1)
Non-cash asset-write-downs	0.0
Balance, March 31, 2019	1.5
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	0.3	2.0
Asset impairment charges, equipment		0.1
Other charges	0.3	1.2
Restructuring and related charges	0.6	$ 3.3
Restructuring Reserve [Roll Forward]
Balance, December 31, 2018	2.3
Charges	0.6
Cash payments	(1.1)
Non-cash asset-write-downs	(0.3)
Balance, March 31, 2019	1.5
2018 Restructuring Plan [Member] | Asset-related charges [Member]
Restructuring Reserve [Roll Forward]
Balance, December 31, 2018	0.0
Charges	0.0
Non-cash asset-write-downs	0.0
Balance, March 31, 2019	0.0
2018 Restructuring Plan [Member] | Other charges [Member]
Restructuring Reserve [Roll Forward]
Balance, December 31, 2018	0.0
Charges	0.3
Non-cash asset-write-downs	(0.3)
Balance, March 31, 2019	0.0
2018 Restructuring Plan [Member] | Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost			$ 15.0
2016 Restructuring Plan [Member]
Restructuring Reserve [Roll Forward]
Balance, March 31, 2019	$ 0.3