Contingencies (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Loss Contingencies [Line Items]
Loss contingency accrual	$ 21.2	$ 32.9
Current portion of contingency reserves	(4.0)	(7.0)
Long-term portion of contingency reserves	17.2	25.9
Reserve for Environmental Costs [Member]
Loss Contingencies [Line Items]
Loss contingency accrual	15.0	14.3	14.7	6.5
Hardboard Siding Reserves [Member]
Loss Contingencies [Line Items]
Loss contingency accrual	6.2	17.8	24.2	31.2
Other Reserves [Member]
Loss Contingencies [Line Items]
Loss contingency accrual	$ 0	$ 0.8