Business Segment Information (Summary Of Intercompany Segment Revenues) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Net revenues	$ (182,462)	$ (340,837)	$ (538,119)	$ (899,996)
Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	14,876	20,193	42,895	57,093
Well Intervention [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	7,324	8,635	18,687	22,052
Robotics [Member] | Intercompany Elimination [Member]
Segment Reporting Information [Line Items]
Net revenues	$ 7,552	$ 11,558	$ 24,208	$ 35,041