Selected Financial Information Regarding the Results of Operations of Former B&W Business (Detail) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total Income (loss) from discontinued operations, net of tax	$ 1,187	$ (40,030)	$ 6,459	$ (34,308)
The Babcock and Wilcox Company
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues		173,540		1,524,424
Loss on disposal of discontinued operations		(5,246)		(95,666)
Income before provision for income taxes		(12,342)		105,796
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax, Total		(17,588)		10,130
Provision for income taxes		4,126		(22,755)
Total Income (loss) from discontinued operations, net of tax		$ (13,462)		$ (12,625)