Business Segment Information - Schedule of Depreciation and Capital Expenditure (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation	$ 11,406	$ 11,234	$ 12,062
Capital expenditures	14,096	16,479	14,937
KSW [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation	9,364	9,160	9,874
Capital expenditures	12,311	14,720	13,456
EWP [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation	1,271	1,397	1,593
Capital expenditures	648	289	528
Calumet [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation	702	576	481
Capital expenditures	1,137	1,470	953
Corporate [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Depreciation	$ 69	$ 101	$ 114