Long-Term Debt (Schedule of Long-Term Debt) (Details) (USD $) In Thousands, unless otherwise specified									12 Months Ended			12 Months Ended			12 Months Ended			12 Months Ended				12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011	Dec. 31, 2012 Helix [Member]	Dec. 31, 2011 Helix [Member]	Dec. 31, 2012 Convertible Senior Notes 2032 [Member]		Mar. 31, 2012 Convertible Senior Notes 2032 [Member]	Dec. 31, 2012 Helix Term Loan [Member]		Dec. 31, 2011 Helix Term Loan [Member]	Dec. 31, 2012 Revolving Credit Facility [Member]	Dec. 31, 2012 2025 Notes [Member]	Dec. 31, 2011 2025 Notes [Member]	Dec. 31, 2012 2032 Notes [Member]	Dec. 31, 2012 Helix Revolving Loans [Member]		Dec. 31, 2012 Senior Unsecured Notes [Member]	Dec. 31, 2011 Senior Unsecured Notes [Member]	Dec. 31, 2010 Senior Unsecured Notes [Member]	Dec. 31, 2011 Convertible Senior Notes 2025 [Member]	Dec. 31, 2012 MARAD Debt [Member]	Dec. 31, 2011 MARAD Debt [Member]
Debt Instrument [Line Items]
Total debt	$ 1,019,228		$ 1,155,321						$ 367,181		$ 279,750	$ 100,000	$ 3,487	$ 300,000	$ 200,000			$ 274,960	$ 474,960			$ 105,288	$ 110,166
Current maturities	(16,607)		(7,877)
Long-term debt, less current maturities	1,002,621		1,147,444	902,453	1,042,155	168,312	[1]		359,181	[2]						100,000	[2]	274,960	475,000	550,000		100,168
Unamortized debt discount	$ (31,688)	[3]	$ (9,555)			$ (31,688)	[1],[3]	$ (35,400)													$ (9,600)
Maturity date									July 2015			July 2015	December 2025		March 2032			January 2016				February 2027

[1] Beginning in March 2018, the holders of these Convertible Senior Notes may require us to repurchase these notes or we may at our own option elect to repurchase notes. These notes will mature in March 2032.

[2] Term Loan amounts reflect both our Term Loan A and Term Loan B. In February 2013, we repaid $293.9 million of our Term Loans and $24.5 million under our Revolving Credit Facility with the after-tax proceeds from the sale of ERT.

[3] The notes will increase to their principal amount through accretion of non-cash interest charges through March 2018 for the Convertible Senior Notes due 2032.