Contingencies (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Loss Contingencies [Line Items]
Loss contingency accrual	$ 14.8	$ 21.2
Current portion of contingency reserves	(2.0)	(4.0)
Long-term portion of contingency reserves	12.8	17.2
Reserve for Environmental Costs [Member]
Loss Contingencies [Line Items]
Loss contingency accrual	14.1	15.0	14.3	14.7
Hardboard Siding Reserves [Member]
Loss Contingencies [Line Items]
Loss contingency accrual	$ 0.7	$ 6.2	$ 17.8	$ 24.2