Operations by Business Segment and Geographic Area Operations by Business Segment and Geographic Area - Other Significant Reconciling Items (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	$ 526,645	$ 207,180	$ 175,021
Oil And Gas [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	514,348	204,236	169,829
ROVs [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	135,770	109,377	146,707
Subsea Products [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	100,824	41,802	13,694
Subsea Projects [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	64,803	43,506	2,817
Asset Integrity [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	212,951	9,551	6,611
Advanced Technologies [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	5,757	2,351	3,234
Corporate and Other [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Capital Expenditures	$ 6,540	$ 593	$ 1,958