Restructuring Costs and Other - By Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 3.0	$ 0.7
Cost of goods sold
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.7	0.8
Selling & administrative expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2.3	(0.1)
Electrical Segment
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1.2	0.7
Electrical Segment | Cost of goods sold
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.2	0.8
Electrical Segment | Selling & administrative expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1.0	(0.1)
Power Segment
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1.8	0.0
Power Segment | Cost of goods sold
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.5	0.0
Power Segment | Selling & administrative expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 1.3	$ 0.0