Business Segment Information - Financial Data By Business Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Revenue	$ 853,297	$ 820,372	$ 734,217	$ 2,392,221	$ 2,001,655
Income from Operations	153,736	146,337	123,813	408,363	309,847
Oil And Gas [Member]
Segment Reporting Information [Line Items]
Revenue	780,439	743,114	655,573	2,170,490	1,792,450
Income from Operations	183,520	171,908	149,886	488,001	383,757
ROVs [Member]
Segment Reporting Information [Line Items]
Revenue	254,979	242,163	224,649	726,770	627,422
Income from Operations	74,710	69,219	66,724	209,764	187,825
Subsea Products [Member]
Segment Reporting Information [Line Items]
Revenue	263,671	258,016	215,617	735,692	579,481
Income from Operations	61,737	62,060	50,841	166,576	117,093
Subsea Projects [Member]
Segment Reporting Information [Line Items]
Revenue	143,132	118,195	101,719	349,782	264,843
Income from Operations	30,700	23,990	17,765	66,310	41,301
Asset Integrity [Member]
Segment Reporting Information [Line Items]
Revenue	118,657	124,740	113,588	358,246	320,704
Income from Operations	16,373	16,639	14,556	45,351	37,538
Advanced Technologies [Member]
Segment Reporting Information [Line Items]
Revenue	72,858	77,258	78,644	221,731	209,205
Income from Operations	6,400	10,165	5,393	25,241	15,547
Unallocated Expenses [Member]
Segment Reporting Information [Line Items]
Income from Operations	$ (36,184)	$ (35,736)	$ (31,466)	$ (104,879)	$ (89,457)