Selected Segment Data (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Net sales:	$ 504.6	$ 471.7
Operating profit (loss):	18.9	(33.2)
Other operating charges and credits, net	0.0	(11.6)
(Gain) loss on sale or impairment of long-lived assets, net	0.0	0.1
Other Selling, General and Administrative Expense	(24.0)	(22.7)
Other Nonoperating Expense	(0.5)	(2.2)
Interest income	1.8	1.4
Interest expense, net of capitalized interest	(8.0)	(7.5)
Loss from operations before taxes	14.7	(40.8)
Provision (benefit) for income taxes	4.4	(6.3)
Net loss	10.3	(34.5)
OSB [Member]
Segment Reporting Information [Line Items]
Net sales:	217.0	190.2
Operating profit (loss):	15.3	(28.4)
Siding [Member]
Segment Reporting Information [Line Items]
Net sales:	181.3	173.5
Operating profit (loss):	26.9	32.9
Engineered Wood Products [Member]
Segment Reporting Information [Line Items]
Net sales:	71.8	64.8
Operating profit (loss):	(2.5)	(4.1)
South America [Member]
Segment Reporting Information [Line Items]
Net sales:	30.5	35.9
Operating profit (loss):	5.1	2.4
Other [Member]
Segment Reporting Information [Line Items]
Net sales:	6.1	7.3
Operating profit (loss):	(0.4)	(0.9)
Intersegment elimination [Member]
Segment Reporting Information [Line Items]
Net sales:	$ (2.1)	$ 0.0