Financial Instruments (Details) (USD $) In Millions, unless otherwise specified			12 Months Ended		12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2010 Interest Rate Swaps	Aug. 31, 2010 Interest Rate Swaps	Dec. 31, 2011 FX forward contracts	Dec. 31, 2010 FX forward contracts	Dec. 31, 2011 FX embedded derivatives	Dec. 31, 2010 FX embedded derivatives	Dec. 31, 2011 Commodity contracts pound	Dec. 31, 2010 Commodity contracts pound
Interest rate swaps
Fixed rate of interest on derivatives (as a percent)				4.795%
Cash payment including accrued interest on terminated swaps			$ 26.9
Accrued interest			2.6
Charge to earnings			24.3
Derivative disclosures
Aggregate notional amount					66.1	199.5	73.2	200.9
Derivative contracts maturities in 2012					59.7		55.0
Derivative contracts maturities in 2013					6.4		15.8
Derivative contracts maturities in 2014							2.4
Unrealized loss, net of tax, recorded in AOCI related to commodity and FX forward contracts	4.4	3.3			3.7	4.1			0.7	(0.8)
Notional amount of commodity contracts (in pounds of copper)									2,900,000	1,800,000
Fair value of derivative contract									(0.8)	1.0
Unrealized loss reclassified into income over the next 12 months	2.8
Percentage of strength of U.S. Dollar against GBP from inception of agreement					4.00%
Cash payment resulting from settlement of contracts					$ 34.6