Condensed Consolidated Guarantor And Non-Guarantor Financial Information (Schedule Of Condensed Consolidating Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Cash and cash equivalents	$ 649,503	$ 546,465	$ 414,189	$ 391,085
Accounts receivable, net	187,904	238,781
Unbilled revenue	51,545	37,375
Other current assets	117,979	121,621
Total current assets	1,006,931	944,242
Property and equipment, net	2,359,293	2,331,327
Equity investments in unconsolidated affiliates	173,543	175,656
Goodwill, net	62,252	62,215
Other assets, net	86,786	68,907
Total assets	3,688,805	3,582,347
Accounts payable	156,738	147,043
Accrued liabilities	177,225	239,963
Income taxes payable	3,065	1,293
Current maturities of long-term debt	12,997	7,877
Total current liabilities	350,025	396,176
Long-term debt	1,167,908	1,147,444
Deferred tax liabilities	445,817	417,610
Asset retirement obligations	135,235	161,208
Other long-term liabilities	8,832	9,368
Total liabilities	2,107,817	2,131,806
Convertible preferred stock	1,000	1,000
Total equity	1,579,988	1,449,541
Total liabilities and shareholders' equity	3,688,805	3,582,347
Helix [Member]
Cash and cash equivalents	584,113	495,484	387,772	376,434
Accounts receivable, net	71,410	79,290
Unbilled revenue	10,416	10,530
Income taxes receivable	111,850	80,388
Other current assets	57,286	68,627
Total current assets	835,075	734,319
Intercompany	(183,504)	(147,187)
Property and equipment, net	223,058	230,946
Equity investments in affiliates	2,031,892	1,952,392
Other assets, net	53,241	53,425
Due from subsidiaries/parent	47,426	64,655
Total assets	3,007,188	2,888,550
Accounts payable	49,247	39,280
Accrued liabilities	59,212	115,921
Current maturities of long-term debt	8,000	3,000
Total current liabilities	116,459	158,201
Long-term debt	1,065,148	1,042,155
Deferred tax liabilities	240,263	231,255
Other long-term liabilities	4,237	4,150
Total liabilities	1,426,107	1,435,761
Convertible preferred stock	1,000	1,000
Total equity	1,580,081	1,451,789
Total liabilities and shareholders' equity	3,007,188	2,888,550
Guarantors [Member]
Cash and cash equivalents	2,775	2,434	2,413	3,294
Accounts receivable, net	82,343	117,767
Unbilled revenue	187	155
Other current assets	44,058	48,661
Total current assets	129,363	169,017
Intercompany	368,513	315,821
Property and equipment, net	1,458,080	1,422,326
Equity investments in affiliates	43,534	37,239
Goodwill, net	45,107	45,107
Other assets, net	38,923	36,453
Due from subsidiaries/parent	580,277	430,496
Total assets	2,663,797	2,456,459
Accounts payable	71,377	82,750
Accrued liabilities	95,392	97,692
Income taxes payable	139,280	97,692
Total current liabilities	306,049	278,134
Deferred tax liabilities	103,693	88,625
Asset retirement obligations	135,235	161,208
Other long-term liabilities	4,067	4,647
Total liabilities	549,044	532,614
Total equity	2,114,753	1,923,845
Total liabilities and shareholders' equity	2,663,797	2,456,459
Non-Guarantors [Member]
Cash and cash equivalents	62,615	48,547	24,004	11,357
Accounts receivable, net	34,151	41,724
Unbilled revenue	40,942	26,690
Income taxes receivable	8,463
Other current assets	16,630	10,159
Total current assets	162,801	127,120
Intercompany	(119,650)	(102,826)
Property and equipment, net	682,846	682,899
Equity investments in unconsolidated affiliates	173,543	175,656
Goodwill, net	17,145	17,108
Other assets, net	32,066	16,809
Total assets	948,751	916,766
Accounts payable	36,114	25,013
Accrued liabilities	22,621	26,350
Income taxes payable		217
Current maturities of long-term debt	4,997	10,377
Total current liabilities	63,732	61,957
Long-term debt	102,760	105,289
Deferred tax liabilities	107,317	103,552
Other long-term liabilities	528	571
Due to parent	81,056	98,285
Total liabilities	355,393	369,654
Total equity	593,358	547,112
Total liabilities and shareholders' equity	948,751	916,766
Consolidating Entries [Member]
Income taxes receivable	(120,313)	(80,388)
Other current assets	5	(5,826)
Total current assets	(120,308)	(86,214)
Intercompany	(65,359)	(65,808)
Property and equipment, net	(4,691)	(4,844)
Equity investments in affiliates	(2,075,426)	(1,989,631)
Other assets, net	(37,444)	(37,780)
Due from subsidiaries/parent	(627,703)	(495,151)
Total assets	(2,930,931)	(2,679,428)
Income taxes payable	(136,215)	(96,616)
Current maturities of long-term debt		(5,500)
Total current liabilities	(136,215)	(102,116)
Deferred tax liabilities	(5,456)	(5,822)
Due to parent	(81,056)	(98,285)
Total liabilities	(222,727)	(206,223)
Total equity	(2,708,204)	(2,473,205)
Total liabilities and shareholders' equity	$ (2,930,931)	$ (2,679,428)