v2.3.0.15

Property And Equipment (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Property and equipment	$ 14,234.0	$ 6,744.6
Equipment Semisubmersible Rigs	12
Equipment Drillships	seven
Equipment Jackup Rigs	seven
Drilling Rigs And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	12,572.2	5,175.2
Property, Plant and Equipment, Gross, Period Increase (Decrease)	7,400.0
Drilling Rigs And Equipment [Member] | Pride [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	5,500.0
Drilling Rigs And Equipment [Member] | ENSCO 8500 [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	1,400.0
Other [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	89.6	50.4
Work In Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	1,572.2	1,519.0
Property, Plant and Equipment, Gross, Period Increase (Decrease)	53.2
Work In Progress [Member] | Pride [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	1,300.0
Work In Progress [Member] | ENSCO 8500 [Member]
Property, Plant and Equipment [Line Items]
Property and equipment		783.1
Ensco Plc [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	1.8	1.8
Pride [Member]
Property, Plant and Equipment [Line Items]
Equipment Semisubmersible Rigs	12
Equipment Drillships	five
Equipment Jackup Rigs	seven
Ensco Ds-5/6/7 Ultra-Deepwater Semisubmersible Rigs [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	455.5
Jackup Rigs [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 91.5

X

- Definition

Equipment Drillships

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Balance Type:	na
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- Definition

Equipment Jackup Rigs

+ Details

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X

- Definition

Equipment Semisubmersible Rigs

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- Definition

Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 5

-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 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Property, plant and equipment additions minus disposals plus or minus transfers and other changes equals the increase or decrease in property, plant and equipment for the period.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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