Business Segment Information (Summary Of Financial Data By Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		1 Months Ended		9 Months Ended	3 Months Ended				9 Months Ended					3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 Intercompany Elimination [Member]	Sep. 30, 2013 Intercompany Elimination [Member]	Sep. 30, 2014 Intercompany Elimination [Member]	Sep. 30, 2013 Intercompany Elimination [Member]	Sep. 30, 2014 Well Intervention [Member] Operating Segments [Member]	Sep. 30, 2013 Well Intervention [Member] Operating Segments [Member]	Sep. 30, 2014 Well Intervention [Member] Operating Segments [Member]	Sep. 30, 2013 Well Intervention [Member] Operating Segments [Member]	Sep. 30, 2014 Well Intervention [Member] Intercompany Elimination [Member]	Sep. 30, 2013 Well Intervention [Member] Intercompany Elimination [Member]	Sep. 30, 2014 Well Intervention [Member] Intercompany Elimination [Member]	Sep. 30, 2013 Well Intervention [Member] Intercompany Elimination [Member]	Sep. 30, 2014 Robotics [Member] Operating Segments [Member]	Sep. 30, 2013 Robotics [Member] Operating Segments [Member]	Sep. 30, 2014 Robotics [Member] Operating Segments [Member]	Sep. 30, 2013 Robotics [Member] Operating Segments [Member]	Sep. 30, 2014 Robotics [Member] Intercompany Elimination [Member]	Sep. 30, 2013 Robotics [Member] Intercompany Elimination [Member]	Sep. 30, 2014 Robotics [Member] Intercompany Elimination [Member]	Sep. 30, 2013 Robotics [Member] Intercompany Elimination [Member]	Jul. 31, 2013 Subsea Construction [Member]	Jun. 30, 2013 Subsea Construction [Member]	Sep. 30, 2014 Subsea Construction [Member]	Sep. 30, 2014 Subsea Construction [Member] Operating Segments [Member]		Sep. 30, 2013 Subsea Construction [Member] Operating Segments [Member]		Sep. 30, 2014 Subsea Construction [Member] Operating Segments [Member]		Sep. 30, 2013 Subsea Construction [Member] Operating Segments [Member]		Sep. 30, 2013 Subsea Construction [Member] Intercompany Elimination [Member]	Sep. 30, 2014 Production Facilities [Member] Operating Segments [Member]	Sep. 30, 2013 Production Facilities [Member] Operating Segments [Member]	Sep. 30, 2014 Production Facilities [Member] Operating Segments [Member]	Sep. 30, 2013 Production Facilities [Member] Operating Segments [Member]	Sep. 30, 2013 Production Facilities [Member] Intercompany Elimination [Member]	Sep. 30, 2014 Corporate and Other [Member] Operating Segments [Member]	Sep. 30, 2013 Corporate and Other [Member] Operating Segments [Member]	Sep. 30, 2014 Corporate and Other [Member] Operating Segments [Member]	Sep. 30, 2013 Corporate and Other [Member] Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	$ 340,837	$ 220,117	$ 899,996	$ 649,724	$ (20,193)	$ (12,977)	$ (57,093)	$ (51,347)	$ 205,139	$ 114,238	$ 546,057	$ 319,893	$ (8,635)	$ (4,784)	$ (22,052)	$ (15,052)	$ 131,707	$ 90,370	$ 339,301	$ 242,940	$ (11,558)	$ (8,193)	$ (35,041)	$ (31,305)						$ 4,120		$ 358		$ 69,305		$ (317)	$ 24,184	$ 24,366	$ 71,373	$ 68,933	$ (4,673)
Income (loss) from operations	106,331	62,659	252,035	125,094	103	21	(1,050)	(2,538)	80,789	33,544	194,297	93,906					28,397	16,392	60,415	28,991								41	[1]	15,088	[1]	10,871	[1]	29,031	[1]		11,284	14,136	33,127	39,964		(14,283)	(16,522)	(45,625)	(64,260)
Equity in earnings of investments	508	857	709	2,150
Gain (loss) on disposition of assets, net		$ 15,812	$ 10,418	$ 14,727																					$ 15,600	$ (1,100)	$ 10,500

[1] Amount in 2014 includes the $10.5 million gain on the sale of our Ingleside spoolbase in January 2014. Amounts in 2013 include the $1.1 million loss on the sale of the Caesar in June 2013 and the $15.6 million gain on the sale of the Express in July 2013.