Business Segment Information (Intercompany Segment Gross Profit (Loss)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]
Gross profit	$ (126,247)	$ (69,457)	$ (311,231)	$ (189,521)
Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit	(103)	(21)	1,050	2,538
Well Intervention [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit	(87)	(45)	(236)	(91)
Robotics [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Gross profit	28	67	1,417	2,602
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	$ (44)	$ (43)	$ (131)	$ (131)