Commitments And Contingencies (Narrative) (Details) (USD $)	9 Months Ended			9 Months Ended	1 Months Ended		14 Months Ended	19 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Collectibility of Receivables [Member]	Sep. 30, 2013 Q7000 [Member]	Aug. 31, 2012 Helix 534 [Member]	Sep. 30, 2013 Helix 534 [Member]	Sep. 30, 2013 Q5000 [Member]	Sep. 30, 2013 Q5000 [Member]	Dec. 31, 2010 Allowance for Doubtful Accounts [Member]
Commitments And Contingencies [Line Items]
Long-term Purchase Commitment, Amount				$ 346,000,000				$ 386,500,000
Property and equipment	1,913,000,000	2,051,796,000		74,400,000		184,700,000	207,600,000	207,600,000
Payments to Acquire Property, Plant, and Equipment				69,200,000	85,000,000		173,800,000
Trade receivables collected	303,000,000
Valuation Allowances and Reserves, Deductions									4,000,000
Value added tax assessment	28,000,000
Accounts Receivable Net Current	$ 150,625,000	$ 152,233,000	$ 17,500,000