Restructuring and Repositioning Expenses, Asset Impairments - Repositioning and Restructuring (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	$ 0.2	$ 2.1
Cash paid	0.7	$ 1.3
2019 Plan, Repositioning
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.2		$ 1.3	$ 1.6	$ 3.3
Cash paid	1.2		1.9	4.5	2.1
2019 Plan, Capital Expenditures
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.5		0.2	0.9	0.3
Cash paid	0.5		0.2	0.8	0.2
2019 Plan Phase 2, Repositioning
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.7		0.0	1.9	0.0
Cash paid	1.3		0.0	2.8	0.0
2019 Plan Phase 2, Capital Expenditures
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.2		0.0	0.3	0.0
Cash paid	0.1		0.0	0.2	0.0
Strategic Alternatives Plan
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.0		2.5	0.0	2.5
Cash paid	0.8		0.0	1.0	0.0
Strategic Alternatives, Capital Expenditures
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.0		0.0	0.0	0.0
Cash paid	0.0		0.0	0.0	0.0
2018 Plan, Repositioning
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.1		1.8	0.1	5.1
Cash paid	0.0		2.6	0.0	7.7
2017 Plan, Repositioning
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.0		0.2	0.1	0.3
Cash paid	0.2		0.3	0.2	1.5
2018 Plan, Capital Expenditures
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.2		0.0	0.5	0.0
Cash paid	0.3		0.0	0.4	0.0
2017 Plan, Capital Expenditures
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.7		0.9	0.9	1.9
Cash paid	0.6		1.0	1.2	1.1
Repositioning
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	1.0		5.8	3.7	11.2
Cash paid	3.5		4.8	8.5	11.3
Capital Expenditures
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	1.6		1.1	2.6	2.2
Cash paid	$ 1.5		$ 1.2	$ 2.6	$ 1.3