Earnings Per Share (Computations Of Basic And Diluted EPS) (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
Earnings Per Share [Abstract]
Net income applicable to Helix	$ 57,782	$ 27,211	$ 111,501	$ 28,826
Income from discontinued operations		29		(1,029)
Net income from continuing operations	57,782	27,240	111,501	27,797
Less: Undistributed net income allocable to participating securities	(300)	(203)	(586)	(201)
Net income applicable to common shareholders - continuing operations	57,482	27,037	110,915	27,596
Less: Undistributed net income from discontinued operations allocable to participating securities				(7)
Net income applicable to common shareholders - discontinued operations				1,022
Weighted average number of shares outstanding - basic	104,992	105,046	105,059	105,039
Share-based awards other than participating securities, Shares	303	87	300	102
Undistributed earnings reallocated to participating securities, value	1		2	1
Net income applicable to Helix - Diluted	57,483	27,037	110,917	27,597
Weighted average number of shares outstanding, diluted, total	105,295	105,133	105,359	105,141
Income from discontinued operations, net of tax		$ (29)		$ 1,029