Commitments and Contingencies (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Changes in the accrued product quality issue
Total accrued product quality issue as of beginning of the period	$ 16.0	$ 21.6
Product quality claims	(5.7)	(5.6)
Change in estimates associated with pre-existing liabilities	(2.8)
Total accrued product quality issue as of ending of the period	$ 7.5	$ 16.0