Business Segment Information (Intercompany Segment Gross Profit (Loss)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]
Gross profit	$ (109,138)	$ (67,497)	$ (184,984)	$ (120,064)
Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit	(45)	839	1,153	2,559
Well Intervention [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit	(87)	(27)	(149)	(46)
Robotics [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit	85	910	1,389	2,535
Subsea Construction [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit				158
Production Facilities [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit	$ (43)	$ (44)	$ (87)	$ (88)