Other Operating Credits and Charges, Net (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Sep. 30, 2011	Jun. 30, 2013	Jun. 30, 2012
Gain Contingencies [Line Items]
Other Cost and Expense, Operating	$ (0.2)			$ (0.2)	$ 0.5
Inventory Write-down	0	0		(1.6)	0
Depreciation and amortization	(1.5)			(1.5)
Other Expenses	(8.1)	(0.2)		(9.7)	0
Other Operating Income (Expense), Net	(5.4)	(0.2)		(7.0)	0
Product Warranty Accrual, Period Increase (Decrease)	(4.1)	0	1.0	(4.1)	0
OSB Mills Construction Related Legal Reserves [Member]
Gain Contingencies [Line Items]
Other Cost and Expense, Operating		0.2
Severance					(0.3)
Construction related legal reserves	0	0		0	0.5
AbitibiBowater-LP [Member]
Gain Contingencies [Line Items]
Other Operating Credits and Charges Associated with Unconsolidated Affiliates	(1.8)	0		(1.8)	0
Canfor-LP [Member]
Gain Contingencies [Line Items]
Other Operating Credits and Charges Associated with Unconsolidated Affiliates	(0.9)	0		(0.9)	0
Unconsolidated Affiliates [Member]
Gain Contingencies [Line Items]
Other Operating Credits and Charges Associated with Unconsolidated Affiliates	$ (2.7)	$ 0		$ (2.7)	$ 0