COMMITMENTS AND CONTINGENCIES - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Jan. 10, 2007 Antoine, et al. vs. J. Ray McDermott, Inc., et al. LegalMatter	Jan. 29, 2007 Antoine, et al. vs. J. Ray McDermott, Inc., et al. Judicial District Court for Harris County, Texas LegalMatter	Jan. 29, 2007 Antoine, et al. vs. J. Ray McDermott, Inc., et al. Judicial District Court for Harris County, Texas Other Employers than JRMI and MI LegalMatter	Jan. 29, 2007 Antoine, et al. vs. J. Ray McDermott, Inc., et al. Judicial District Court for Harris County, Texas Maritime products LegalMatter	Jan. 29, 2007 Boudreaux, et al. v. McDermott, Inc., et al. United States District Court for the Southern District of Texas LegalMatter	Jan. 29, 2007 Boudreaux, et al. v. McDermott, Inc., et al. United States District Court for the Southern District of Texas Other Employers than JRMI and MI LegalMatter	Dec. 31, 2011 Minimum	Dec. 31, 2011 Maximum
Commitments and Contingencies Disclosure [Line Items]
Legal claims		On December 16, 2005, a proceeding entitled Antoine, et al. vs. J. Ray McDermott, Inc., et al.(“Antoine Suit”), was filed in the 24th Judicial District Court, Jefferson Parish, Louisiana, by approximately 88 plaintiffs against approximately 215 defendants, including our subsidiaries formerly known as J. Ray McDermott (“JRMI”) and Delta Hudson Engineering Corporation (“DHEC”), generally alleging injuries for exposure to asbestos, and unspecified chemicals, metals and noise while the plaintiffs were allegedly employed as Jones Act seamen. This case was dismissed by the Court on January 10, 2007, without prejudice to plaintiffs’ rights to refile their claims. On January 29, 2007, 21 plaintiffs from the dismissed Antoine Suit filed a matter entitled Boudreaux, et al. v. McDermott, Inc., et al. (the “Boudreaux Suit”), in the United States District Court for the Southern District of Texas, against JRMI and our subsidiary formerly known as McDermott Incorporated, and approximately 30 other employer defendants, alleging Jones Act seaman status and generally alleging exposure to welding fumes, solvents, dyes, industrial paints and noise. The Boudreaux Suit was transferred to the United States District Court for the Eastern District of Louisiana on May 2, 2007, which entered an order in September 2007 staying the matter until further order of the Court due to the bankruptcy filing of one of the co-defendants.
Number of plaintiffs					88	43			21
Number of defendants					215		65	42		30
Environmental reserves	$ 1.3	$ 1.3	$ 2.9
Environmental reserves, current	1.3	1.3	2.4
Environmental reserves, recovery	2.0	2.0
Aggregate possible liquidated damage due to failure to meet specified contractual milestone dates, offshore oil and gas construction segment	66	66
Liquidated damage contingencies, accrued	17	17
Decrease in potential liquidated damages	28
Total rental expense		53.9	47.9	54.1
Trigger dates, potential liquidated damages											2011-04	2012-12
Surety bonds issued	$ 0	$ 0