Dispositions and Other Items - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended	3 Months Ended	1 Months Ended	3 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended			1 Months Ended
	Jul. 30, 2010	Dec. 31, 2012 Vessel	Dec. 31, 2011	Dec. 31, 2010	Aug. 26, 2011 Marine Vessels	Dec. 31, 2011 Marine Vessels	Sep. 30, 2012 Multi Function Support Vessel Vessel	Jan. 31, 2013 Multi Function Support Vessel Subsequent Event	Sep. 30, 2010 Fabrication Operations	Dec. 31, 2011 Fabrication Operations	Mar. 19, 2012 Charter Fleet Business Vessel	Dec. 31, 2012 Charter Fleet Business	Dec. 31, 2011 Charter Fleet Business	Dec. 31, 2010 Charter Fleet Business	Mar. 19, 2012 Secunda International Limited Vessel
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of vessels held for sale		2					3
Assets held for sale		$ 30,000,000
Proceeds from sale of discontinued assets								2,000,000
Proceeds from sale of business					8,000,000
Gain (loss) on disposal of discontinued operations		257,000	(21,934,000)	(123,311,000)		7,700,000						257,000	(21,934,000)	(27,690,000)
Costs to discontinue development plans for a new fabrication yard, including estimated lease termination costs									21,000,000
Reduced estimated closure costs										10,000,000
Number of vessels sold											10
Number of vessels															14
Cash contribution from The Babcock & Wilcox Company	$ 100,000,000			$ 100,000,000