Restructuring Costs and Other - Summary of Costs (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Total expected costs	$ 56.0
Costs incurred	12.5	$ 32.0
Remaining costs at 9/30/2020	11.5
2020 Restructuring Actions
Restructuring Cost and Reserve [Line Items]
Total expected costs	15.5
Costs incurred	8.2	0.0
Remaining costs at 9/30/2020	7.3
2020 Restructuring Actions | Electrical
Restructuring Cost and Reserve [Line Items]
Total expected costs	14.8
Costs incurred	7.5	0.0
Remaining costs at 9/30/2020	7.3
2020 Restructuring Actions | Utility Solutions
Restructuring Cost and Reserve [Line Items]
Total expected costs	0.7
Costs incurred	0.7	0.0
Remaining costs at 9/30/2020	0.0
2019 and Prior Restructuring Actions
Restructuring Cost and Reserve [Line Items]
Total expected costs	40.5
Costs incurred	4.3	32.0
Remaining costs at 9/30/2020	4.2
2019 and Prior Restructuring Actions | Electrical
Restructuring Cost and Reserve [Line Items]
Total expected costs	20.7
Costs incurred	(0.1)	20.5
Remaining costs at 9/30/2020	0.3
2019 and Prior Restructuring Actions | Utility Solutions
Restructuring Cost and Reserve [Line Items]
Total expected costs	19.8
Costs incurred	4.4	$ 11.5
Remaining costs at 9/30/2020	$ 3.9