Long-Term Debt (Maturities Of Long-Term Debt) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012	Mar. 31, 2013 Helix Term Loan [Member]		Mar. 31, 2013 Helix Revolving Loans [Member]		Mar. 31, 2013 Senior Unsecured Notes [Member]	Mar. 31, 2013 MARAD Debt [Member]	Mar. 31, 2013 Convertible Senior Notes 2032 [Member]		Mar. 31, 2012 Convertible Senior Notes 2032 [Member]	Mar. 31, 2013 Helix [Member]	Dec. 31, 2012 Helix [Member]
Debt Instrument [Line Items]
Less than one year	$ 10,247	[1]		$ 5,000	[2]				$ 5,247
One to two years	10,508	[1]		5,000	[2]				5,508
Two to three years	421,142	[1]		62,299	[2]	78,100	[2]	274,960	5,783
Three to four years	6,072	[1]							6,072
Four to five years	6,375	[1]							6,375
Over five years	273,774	[1]							73,774	200,000
Total debt	728,118	[1]		72,299	[2]	78,100	[2]	274,960	102,759	200,000
Current maturities	(10,247)	[1]	(16,607)	(5,000)	[2]				(5,247)				(5,000)	(11,487)
Long-term debt, less current maturities	717,871	[1]		67,299	[2]	78,100	[2]	274,960	97,512	200,000
Unamortized debt discount	(30,410)	[1],[3]								(30,410)	[3]	(35,400)
Long-term debt	$ 687,461	[1]	$ 1,002,621	$ 67,299	[2]	$ 78,100	[2]	$ 274,960	$ 97,512	$ 169,590			$ 589,948	$ 902,453

[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] Amounts reflect our remaining Term Loan debt. In February 2013, we repaid $293.9 million of our Term Loan debt 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.