Plant Closure Provisions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Movements in plant closure and restructuring provisions
Beginning Balance	$ 28.6	$ 27.5	$ 28.4
Charge for the period	4.2	5.1	3.0
Expenditure	(2.7)	(3.8)	(3.9)
Exchange effect	0.3	(0.2)	0
Ending Balance	30.4	28.6	27.5
Due within one year	(5.1)	(4.1)	(3.9)
Balance at December 31	25.3	24.5	23.6
Severance [Member]
Movements in plant closure and restructuring provisions
Beginning Balance	1.5	1.5	1.3
Charge for the period	0.2	0.7	0.5
Expenditure	(0.6)	(0.7)	(0.4)
Exchange effect	0	0	0.1
Ending Balance	1.1	1.5	1.5
Due within one year	(0.1)	(0.5)	(0.5)
Balance at December 31	1.0	1.0	1.0
Other Restructuring [Member]
Movements in plant closure and restructuring provisions
Beginning Balance	0	0.1	1.0
Charge for the period	0	(0.1)	0
Expenditure	0	0	(0.8)
Exchange effect	0	0	(0.1)
Ending Balance	0	0	0.1
Due within one year	0	0	(0.1)
Balance at December 31	0	0	0
Remediation [Member]
Movements in plant closure and restructuring provisions
Beginning Balance	27.1	25.9	26.1
Charge for the period	4.0	4.5	2.5
Expenditure	(2.1)	(3.1)	(2.7)
Exchange effect	0.3	(0.2)	0
Ending Balance	29.3	27.1	25.9
Due within one year	(5.0)	(3.6)	(3.3)
Balance at December 31	$ 24.3	$ 23.5	$ 22.6

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References+ Details

Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References+ Details

- Definition

Amount of cash paid in the period to fully or partially settle a specified, previously accrued type of restructuring cost.

+ References+ Details

- Definition

Amount of foreign currency translation adjustment increasing or decreasing the accrual for a specified type of restructuring cost.

+ References+ Details