Restructuring Costs and Other - Summary of Costs (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Total expected costs	$ 39.2
Costs incurred	13.9	$ 19.2
Remaining costs at 9/30/2016	6.1
2016 Restructuring Actions
Restructuring Cost and Reserve [Line Items]
Total expected costs	15.2
Costs incurred	12.0	0.0
Remaining costs at 9/30/2016	3.2
2016 Restructuring Actions | Electrical
Restructuring Cost and Reserve [Line Items]
Total expected costs	14.0
Costs incurred	11.0	0.0
Remaining costs at 9/30/2016	3.0
2016 Restructuring Actions | Power
Restructuring Cost and Reserve [Line Items]
Total expected costs	1.2
Costs incurred	1.0	0.0
Remaining costs at 9/30/2016	0.2
2015 and Prior Restructuring Actions
Restructuring Cost and Reserve [Line Items]
Total expected costs	24.0
Costs incurred	1.9	19.2
Remaining costs at 9/30/2016	2.9
2015 and Prior Restructuring Actions | Electrical
Restructuring Cost and Reserve [Line Items]
Total expected costs	22.1
Costs incurred	1.9	17.3
Remaining costs at 9/30/2016	2.9
2015 and Prior Restructuring Actions | Power
Restructuring Cost and Reserve [Line Items]
Total expected costs	1.9
Costs incurred	0.0	$ 1.9
Remaining costs at 9/30/2016	$ 0.0