Segment Information (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net sales and long-lived assets by geographical area
Net Sales	$ 160,322	$ 195,877	$ 195,596	$ 154,535	$ 144,686	$ 172,113	$ 181,703	$ 158,734	$ 706,329	$ 657,236	$ 603,446
Long-Lived Assets	212,122				216,662				212,122	216,662	205,179
Largest customer | Net sales
Net sales and long-lived assets by geographical area
Percentage of net sales attributable to largest customer										10.00%	10.00%
Wood Construction
Net sales and long-lived assets by geographical area
Net Sales									596,849	558,113	536,131
Concrete Construction
Net sales and long-lived assets by geographical area
Net Sales									108,341	97,967	66,031
Other
Net sales and long-lived assets by geographical area
Net Sales									1,139	1,156	1,284
United States
Net sales and long-lived assets by geographical area
Net Sales									531,968	479,390	433,242
Long-Lived Assets	152,644				152,456				152,644	152,456	165,363
Canada
Net sales and long-lived assets by geographical area
Net Sales									41,626	44,359	42,350
Long-Lived Assets	5,763				6,182				5,763	6,182	5,964
Denmark
Net sales and long-lived assets by geographical area
Net Sales									14,993	15,096	17,158
Long-Lived Assets	1,907				2,252				1,907	2,252	2,607
United Kingdom
Net sales and long-lived assets by geographical area
Net Sales									21,852	23,504	23,598
Long-Lived Assets	1,249				1,232				1,249	1,232	1,370
France
Net sales and long-lived assets by geographical area
Net Sales									36,708	37,826	43,319
Long-Lived Assets	9,302				10,036				9,302	10,036	10,530
Germany
Net sales and long-lived assets by geographical area
Net Sales									26,058	27,919	27,237
Long-Lived Assets	17,446				17,651				17,446	17,651	4,957
Switzerland
Net sales and long-lived assets by geographical area
Net Sales									6,019	6,653
Long-Lived Assets	11,649				11,628				11,649	11,628
Poland
Net sales and long-lived assets by geographical area
Net Sales									5,982	4,847	3,004
Long-Lived Assets	692				795				692	795	224
The Netherlands
Net sales and long-lived assets by geographical area
Net Sales									4,306	3,336
Long-Lived Assets	63				92				63	92
Portugal
Net sales and long-lived assets by geographical area
Net Sales									804	1,437
Long-Lived Assets	688				734				688	734
Ireland
Net sales and long-lived assets by geographical area
Net Sales									31	791	2,720
Long-Lived Assets					2,757					2,757	3,075
China/Hong Kong
Net sales and long-lived assets by geographical area
Net Sales									9,802	6,054	4,754
Long-Lived Assets	9,499				9,675				9,499	9,675	10,022
Australia
Net sales and long-lived assets by geographical area
Net Sales									3,289	3,386	4,586
Long-Lived Assets	356				441				356	441	369
New Zealand
Net sales and long-lived assets by geographical area
Net Sales									1,701	1,404	188
Long-Lived Assets	125				154				125	154	138
Other countries
Net sales and long-lived assets by geographical area
Net Sales									1,190	1,234	1,290
Long-Lived Assets	$ 739				$ 577				$ 739	$ 577	$ 560