Plant Turnaround Costs (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Net capitalized turnaround costs:
Balance at the beginning of the period	$ 82.1	$ 54.8
Additions	74.8	29.2
Depreciation	(30.0)	(22.1)
Effect of exchange rate changes	(0.1)	0.4
Balance at the end of the period	$ 126.8	$ 62.3