Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 581.6	$ 691.3
Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	235.6	227.0
OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	208.4	313.3
EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	90.4	105.8
South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	44.6	42.4
Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	4.4	2.8
Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	(1.8)	0.0
SmartSide Strand siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	193.0	172.0
SmartSide Strand siding [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	187.0	165.1
SmartSide Strand siding [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Strand siding [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Strand siding [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	6.0	6.8
SmartSide Strand siding [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Strand siding [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Fiber siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	26.0	26.0
SmartSide Fiber siding [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	25.8	25.9
SmartSide Fiber siding [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Fiber siding [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Fiber siding [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Fiber siding [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
SmartSide Fiber siding [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
CanExel siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	17.0	14.0
CanExel siding [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	16.9	13.9
CanExel siding [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
CanExel siding [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
CanExel siding [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
CanExel siding [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
CanExel siding [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
OSB - commodity [Member]
Disaggregation of Revenue [Line Items]
Revenues	111.0	193.0
OSB - commodity [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	3.0	8.7
OSB - commodity [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	106.9	181.1
OSB - commodity [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	1.7	2.8
OSB - commodity [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
OSB - commodity [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
OSB - commodity [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	(0.9)	0.0
OSB - value-add [Member]
Disaggregation of Revenue [Line Items]
Revenues	138.0	177.0
OSB - value-add [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	9.2
OSB - value-add [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	98.3	129.1
OSB - value-add [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	2.1	4.1
OSB - value-add [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	38.0	34.9
OSB - value-add [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
OSB - value-add [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LVL [Member]
Disaggregation of Revenue [Line Items]
Revenues	31.0	37.0
LVL [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LVL [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LVL [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	30.6	36.6
LVL [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LVL [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LVL [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LSL [Member]
Disaggregation of Revenue [Line Items]
Revenues	12.0	13.0
LSL [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LSL [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LSL [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	13.2	13.3
LSL [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LSL [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
LSL [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	(0.9)	0.0
I Joist [Member]
Disaggregation of Revenue [Line Items]
Revenues	26.0	32.0
I Joist [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
I Joist [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
I Joist [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	26.4	32.1
I Joist [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
I Joist [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
I Joist [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Plywood [Member]
Disaggregation of Revenue [Line Items]
Revenues	7.0	8.0
Plywood [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Plywood [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Plywood [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	6.7	7.6
Plywood [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Plywood [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Plywood [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	20.5	20.0
Other [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	2.9	4.2
Other [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	3.2	3.1
Other [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	9.7	9.3
Other [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.7
Other [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	4.4	2.8
Other [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Commodity [Member]
Disaggregation of Revenue [Line Items]
Revenues	118.0	201.0
Commodity [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	3.0	8.7
Commodity [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	106.9	181.1
Commodity [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	8.4	10.4
Commodity [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Commodity [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Commodity [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	(0.9)	0.0
Value-add [Member]
Disaggregation of Revenue [Line Items]
Revenues	443.1	470.3
Value-add [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	229.7	214.1
Value-add [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	98.3	129.1
Value-add [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	72.3	86.1
Value-add [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	44.3	41.7
Value-add [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.0	0.0
Value-add [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	(0.9)	0.0
Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	20.5	20.0
Other [Member] | Siding [Member]
Disaggregation of Revenue [Line Items]
Revenues	2.9	4.2
Other [Member] | OSB [Member]
Disaggregation of Revenue [Line Items]
Revenues	3.2	3.1
Other [Member] | EWP [Member]
Disaggregation of Revenue [Line Items]
Revenues	9.7	9.3
Other [Member] | South America [Member]
Disaggregation of Revenue [Line Items]
Revenues	0.3	0.7
Other [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	4.4	2.8
Other [Member] | Intersegment [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 0.0	$ 0.0