v2.3.0.15

Contingencies (Narrative) (Details) (USD $) | 1 Months Ended | 9 Months Ended | 12 Months Ended |  |  | 9 Months Ended |  | 1 Months Ended | 9 Months Ended | 1 Months Ended
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Mar. 31, 2009 | Sep. 30, 2011 | Dec. 31, 2006 | Sep. 30, 2009 | Sep. 30, 2011 Reduction In Merger Agreement Payable [Member] | Sep. 30, 2011 Reduction In Merger Termination Period [Member] | Sep. 30, 2011 Number Of Plaintiffs State Courts [Member] | Sep. 30, 2011 Number Of Plaintiffs US District Court [Member] | Jul. 31, 2009 Spain [Member] | Sep. 30, 2011 Brazil [Member] | Sep. 30, 2010 Seahawk [Member]
Oil and Gas Delivery Commitments and Contracts [Line Items] |  |  |  |  |  |  |  |  |  |  |
Distance from original drilling location in miles | 95 |  |  |  |  |  |  |  |  |  |
Property insurance self-insured retention per occurrence |  | $ 50,000,000 |  |  |  |  |  |  |  |  |
Property coverage limit for sue and labor costs - ENSCO 74 |  | 25,000,000 |  |  |  |  |  |  |  |  |
Property coverage limit for wreckage and debris removal costs - ENSCO 74 |  | 50,000,000 |  |  |  |  |  |  |  |  |
Annual liability coverage limit for wreckage and debris removal costs - ENSCO 74 |  | 500,000,000 |  |  |  |  |  |  |  |  |
Merger related fees payable |  | 260,000,000 |  |  | 195,000,000 |  |  |  |  |  |
Maximum fees and expenses unable to be opposed |  | 1,100,000 |  |  |  |  |  |  |  |  |
Merger related termination period |  | 12 |  |  |  | 9 |  |  |  |  |
Minimum estimate leg and debris removal costs |  | 21,000,000 |  |  |  |  |  |  |  |  |
Maximum estimate leg and debris removal costs |  | 35,000,000 |  |  |  |  |  |  |  |  |
Liability and insurance receivable for ENSCO 74 leg removal costs |  | 21,000,000 |  |  |  |  |  |  |  |  |
Civil litigation claim damages for cost of repair and business interruption due to pipeline rupture |  |  |  | 26,000,000 |  |  |  |  |  |  |
Civil litigation damages | 10,000,000 |  |  |  |  |  |  |  |  |  |
Liability insurance self-insured retention per occurrence |  | 10,000,000 |  |  |  |  |  |  |  |  |
Annual liability coverage limit for wreckage and debris removal costs |  | 500,000,000 |  |  |  |  |  |  |  |  |
Liability insurance self-insured retention |  | 15,000,000 |  |  |  |  |  |  |  |  |
Liability insurance self insured retention for each occurrence thereafter |  | 1,000,000 |  |  |  |  |  |  |  |  |
ENSCO 69 insured value, package policy |  | 65,000,000 |  |  |  |  |  |  |  |  |
Packaged policy ENSCO 69 deductible |  | 10,000,000 |  |  |  |  |  |  |  |  |
Minimum estimate of ENSCO 29 wreckage removal costs |  | 5,000,000 |  |  |  |  |  |  |  |  |
Maximum estimate of ENSCO 29 wreckage removal costs |  | 15,000,000 |  |  |  |  |  |  |  |  |
Property coverage limit ENSCO 29 wreckage and debris removal costs |  | 3,800,000 |  |  |  |  |  |  |  |  |
Liability coverage excess ENSCO 29 wreckage and debris removal costs |  | 3,800,000 |  |  |  |  |  |  |  |  |
ENSCO 29 insurance provision |  |  | 1,200,000 |  |  |  |  |  |  |  |
Representation of claim, percentage |  | 10.00% |  |  |  |  |  |  |  |  |
Gain related to litigation settlement |  | 10,800,000 |  |  |  |  |  |  |  |  |
Minimum estimate of removal costs |  |  | 5,000,000 |  |  |  |  |  |  |  |
Initial multi-party asbestos claims |  | 600 |  |  |  |  |  |  |  |  |
Number of plaintiffs |  | 65 |  |  |  |  | 62 | 3 |  |  |
Aggregate amount of fine sought by governmental authorities |  |  |  |  |  |  |  |  |  | 2,000,000 |
Aggregate amount of pending administrative proceeding raised by governmental authority |  |  |  |  |  |  |  |  | 4,000,000 |  |
Environmental liabilities |  | 2,000,000 |  |  |  |  |  |  |  |  |
Line of credit assumed |  |  |  |  |  |  |  |  |  |  | 50,000,000
Line of credit recorded liability |  | $ 700,000 |  |  |  |  |  |  |  |  |

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- Definition The adjustment to exclude the noncash portion of, and include cash payments for environmental costs when calculating operating cash flows under the indirect method. The adjustment can include the increase (decrease) during an accounting period in total estimated obligations recorded for probable future loss attributable to environmental contamination issues. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 + Details
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- Definition The net proceeds or assets obtained in excess of (less than) the net carrying amount of assets recorded, or assets distributed and liabilities assumed less than (in excess of) estimated litigation liability extinguished, in settlement of a litigation matter. Represents (for other than an insurance entity in its normal claims settlement process), the amount of income (expense) recognized in the period to settle pending or threatened litigation and insurance claims. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 5 -Paragraph 9, 10, 11, 12 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349 + Details
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