Derivatives (Outstanding Contracts Designated as Cash Flow Hedges) (Details) - Designated as Hedging Instrument [Member] lb in Millions, $ in Millions, $ in Millions	Mar. 31, 2018 CAD ($) lb	Mar. 31, 2018 MXN ($) lb	Dec. 31, 2017 CAD ($) lb	Dec. 31, 2017 MXN ($) lb
Commodity Contract - Copper [Member]
Derivative [Line Items]
Derivative, nonmonetary notional amount (in lbs) | lb	20.2	20.2	20.6	20.6
Commodity Contract - Aluminum [Member]
Derivative [Line Items]
Derivative, nonmonetary notional amount (in lbs) | lb	16.6	16.6	0.0	0.0
Foreign Exchange Forward [Member] | Mexican Peso [Member]
Derivative [Line Items]
Derivative, notional amount | $		$ 152.2		$ 207.3
Foreign Exchange Forward [Member] | Canadian Dollar [Member]
Derivative [Line Items]
Derivative, notional amount | $	$ 51.0		$ 68.6