Condensed Consolidated Guarantor And Non-Guarantor Financial Information (Schedule Of Condensed Consolidating Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Cash and cash equivalents	$ 620,449	$ 546,465	$ 440,531	$ 391,085
Accounts receivable, net	237,417	238,781
Unbilled revenue	24,576	37,375
Other current assets	109,669	121,621
Total current assets	992,111	944,242
Property and equipment, net	2,361,687	2,331,327
Equity investments in unconsolidated affiliates	173,440	175,656
Goodwill, net	62,667	62,215
Other assets, net	75,038	68,907
Total assets	3,664,943	3,582,347
Accounts payable	145,631	147,043
Accrued liabilities	196,814	239,963
Income taxes payable	24,977	1,293
Current maturities of long-term debt	12,997	7,877
Total current liabilities	380,419	396,176
Long-term debt	1,167,486	1,147,444
Deferred income taxes	423,098	417,610
Asset retirement obligations	146,696	161,208
Other long-term liabilities	16,516	9,368
Total liabilities	2,134,215	2,131,806
Convertible preferred stock	1,000	1,000
Total equity	1,529,728	1,449,541
Total liabilities and shareholders' equity	3,664,943	3,582,347
Helix [Member]
Cash and cash equivalents	566,287	495,484	425,514	376,434
Accounts receivable, net	50,886	79,290
Unbilled revenue	5,777	10,530
Income taxes receivable	86,005	80,388
Other current assets	54,484	68,627
Total current assets	763,439	734,319
Intercompany	(157,195)	(147,187)
Property and equipment, net	227,620	230,946
Equity investments in affiliates	2,019,076	1,952,392
Other assets, net	54,828	53,425
Due from subsidiaries/parent	56,189	64,655
Total assets	2,963,957	2,888,550
Accounts payable	42,316	39,280
Accrued liabilities	68,627	115,921
Current maturities of long-term debt	8,000	3,000
Total current liabilities	118,943	158,201
Long-term debt	1,064,726	1,042,155
Deferred income taxes	234,567	231,255
Other long-term liabilities	4,163	4,150
Total liabilities	1,422,399	1,435,761
Convertible preferred stock	1,000	1,000
Total equity	1,540,558	1,451,789
Total liabilities and shareholders' equity	2,963,957	2,888,550
Guarantors [Member]
Cash and cash equivalents	2,498	2,434	2,473	3,294
Accounts receivable, net	118,038	117,767
Unbilled revenue	228	155
Other current assets	45,654	48,661
Total current assets	166,418	169,017
Intercompany	340,018	315,821
Property and equipment, net	1,456,602	1,422,326
Equity investments in affiliates	39,864	37,239
Goodwill, net	45,107	45,107
Other assets, net	36,566	36,453
Due from subsidiaries/parent	509,701	430,496
Total assets	2,594,276	2,456,459
Accounts payable	67,950	82,750
Accrued liabilities	107,284	97,692
Income taxes payable	128,808	97,692
Total current liabilities	304,042	278,134
Deferred income taxes	90,526	88,625
Asset retirement obligations	146,696	161,208
Other long-term liabilities	11,803	4,647
Total liabilities	553,067	532,614
Total equity	2,041,209	1,923,845
Total liabilities and shareholders' equity	2,594,276	2,456,459
Non-Guarantors [Member]
Cash and cash equivalents	51,664	48,547	12,544	11,357
Accounts receivable, net	68,493	41,724
Unbilled revenue	18,571	26,690
Income taxes receivable	1,586
Other current assets	9,864	10,159
Total current assets	150,178	127,120
Intercompany	(107,547)	(102,826)
Property and equipment, net	682,200	682,899
Equity investments in unconsolidated affiliates	173,440	175,656
Goodwill, net	17,560	17,108
Other assets, net	21,475	16,809
Total assets	937,306	916,766
Accounts payable	35,365	25,013
Accrued liabilities	20,903	26,350
Income taxes payable		217
Current maturities of long-term debt	4,997	10,377
Total current liabilities	61,265	61,957
Long-term debt	102,760	105,289
Deferred income taxes	103,861	103,552
Other long-term liabilities	550	571
Due to parent	89,821	98,285
Total liabilities	358,257	369,654
Total equity	579,049	547,112
Total liabilities and shareholders' equity	937,306	916,766
Consolidating Entries [Member]
Income taxes receivable	(87,591)	(80,388)
Other current assets	(333)	(5,826)
Total current assets	(87,924)	(86,214)
Intercompany	(75,276)	(65,808)
Property and equipment, net	(4,735)	(4,844)
Equity investments in affiliates	(2,058,940)	(1,989,631)
Other assets, net	(37,831)	(37,780)
Due from subsidiaries/parent	(565,890)	(495,151)
Total assets	(2,830,596)	(2,679,428)
Income taxes payable	(103,831)	(96,616)
Current maturities of long-term debt		(5,500)
Total current liabilities	(103,831)	(102,116)
Deferred income taxes	(5,856)	(5,822)
Due to parent	(89,821)	(98,285)
Total liabilities	(199,508)	(206,223)
Total equity	(2,631,088)	(2,473,205)
Total liabilities and shareholders' equity	$ (2,830,596)	$ (2,679,428)