Business Segment Information - Financial Data By Business Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Segment Reporting Information [Line Items]
Revenue	$ 718,552	$ 780,949	$ 594,893
Income from Operations	108,290	118,750	75,987
Oil And Gas [Member]
Segment Reporting Information [Line Items]
Revenue	646,937	705,056	532,184
Income from Operations	132,573	144,831	100,548
ROVs [Member]
Segment Reporting Information [Line Items]
Revenue	229,628	226,098	193,971
Income from Operations	65,835	61,147	56,933
Subsea Products [Member]
Segment Reporting Information [Line Items]
Revenue	214,005	249,553	172,081
Income from Operations	42,779	53,866	29,510
Subsea Projects [Member]
Segment Reporting Information [Line Items]
Revenue	88,455	114,728	72,676
Income from Operations	11,620	22,160	7,567
Asset Integrity [Member]
Segment Reporting Information [Line Items]
Revenue	114,849	114,677	93,456
Income from Operations	12,339	7,658	6,538
Advanced Technologies [Member]
Segment Reporting Information [Line Items]
Revenue	71,615	75,893	62,709
Income from Operations	8,676	5,635	3,509
Unallocated Expenses [Member]
Segment Reporting Information [Line Items]
Income from Operations	$ (32,959)	$ (31,716)	$ (28,070)