Restructuring Costs - By Segment (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	$ 7.8	$ 19.5
Cost of goods sold
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	5.1	13.1
Selling & administrative expense
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	2.7	6.4
Electrical
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	7.2	17.7
Electrical | Cost of goods sold
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	5.0	12.3
Electrical | Selling & administrative expense
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	2.2	5.4
Power
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	0.6	1.8
Power | Cost of goods sold
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	0.1	0.8
Power | Selling & administrative expense
Restructuring Cost and Reserve [Line Items]
Pre-tax Restructuring Costs	$ 0.5	$ 1.0