Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended					3 Months Ended								1 Months Ended	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013 Minimum	Mar. 31, 2013 Maximum	Mar. 31, 2013 Atlantic	Mar. 31, 2012 Atlantic	Mar. 31, 2013 Atlantic Project One	Mar. 31, 2013 Atlantic Project Two	Mar. 31, 2013 Atlantic Deferred profit recognition contracts Project	Mar. 31, 2012 Atlantic Deferred profit recognition contracts	Mar. 31, 2013 Atlantic Backlog	Mar. 19, 2012 Charter Fleet Business Vessel	Mar. 19, 2012 Secunda International Limited Vessel	Mar. 31, 2013 Consolidated Entities	Mar. 31, 2012 Consolidated Entities	Mar. 31, 2013 Unconsolidated joint ventures	Mar. 31, 2012 Unconsolidated joint ventures	Mar. 31, 2013 Unapproved claims	Mar. 31, 2012 Unapproved claims	Mar. 31, 2013 Middle East Project	Mar. 31, 2013 Middle East Project One of Five	Mar. 31, 2013 Middle East Project Three of Five	Mar. 31, 2013 Middle East Project Two of Three	Mar. 31, 2013 Middle East Project One of Three	Mar. 31, 2013 Middle East Project Five of Five	Mar. 31, 2013 Asia Pacific Project
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of vessels operated													10
Number of vessels														14
Percentage of completion to recognize expected profit						70.00%
Number of projects										1											5						2
Revenues	$ 807,488,000	$ 727,678,000				$ 148,184,000	$ 99,604,000			$ 5,300,000	$ 5,200,000	$ 165,600,000			$ 29,000,000	$ 10,000,000	$ 3,700,000	$ 4,000,000	$ 225,800,000	$ 71,000,000
Cost of operations	712,814,000	597,434,000								5,300,000	5,200,000				29,000,000	10,000,000	3,700,000	4,000,000	225,800,000	71,000,000
Recognized project income losses								6,900,000	2,400,000												7,700,000	5,400,000	1,800,000
Increased estimated costs of project																					38,000,000		16,700,000
Changes in estimated cost of completion																						17,500,000				4,100,000	14,000,000
Project completion year																						2013		2013	2014	2013	2013
Project charges																											4,100,000
Equity method of accounting investment ownership				20.00%	50.00%
Accounts receivable - other	65,561,000		75,461,000
Allowance for doubtful accounts	$ 0		$ 0