Fair Value Measurements (Fair Value Of Long Term Debt) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended					1 Months Ended								1 Months Ended
	Mar. 31, 2013		Mar. 31, 2012	Mar. 31, 2013 Term Loan [Member]		Feb. 28, 2013 Helix Revolving Loans [Member]	Mar. 31, 2013 Helix Revolving Loans [Member]		Mar. 31, 2013 Convertible Senior Notes (Matures March 2032) [Member]		Mar. 31, 2013 Senior Unsecured Notes [Member]	Mar. 31, 2013 MARAD Debt [Member]		Feb. 28, 2013 Helix Term Loan [Member]	Mar. 31, 2013 Helix Term Loan [Member]	Mar. 31, 2013 Loan Notes [Member]
Long-term debt, Fair Value				$ 73,022	[1]		$ 78,100	[1]	$ 246,540	[2]	$ 283,896	$ 117,597	[3]			$ 799,155
Long-term debt, Carrying Value				72,299	[1]		78,100	[1]	200,000	[2]	274,960	102,759	[3]		72,300	728,118
Unamortized debt discount	30,410	[4],[5]
Repayment of Helix Term Notes	$ 294,882		$ 750			$ 24,500								$ 293,900

[1] 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.

[2] Carrying value excludes the related unamortized debt discount of $30.4 million at March 31, 2013.

[3] The estimated fair value of all debt, other than the MARAD debt, was determined using Level 1 inputs using the market approach. The fair value of the MARAD debt was determined using a third party evaluation of the remaining average life and outstanding principal balance of the MARAD indebtedness as compared to other governmental obligations in the marketplace with similar terms. The fair value of the MARAD Debt was estimated using Level 2 fair value inputs using the market approach.

[4] 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.

[5] 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.