v2.3.0.15

Segment Information (Schedule Of Geographic Distribution Of Rigs By Segment) (Details)	9 Months Ended
	Sep. 30, 2011
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	76	[1]
Deepwater [Member] | North & South America (Excl. Brazil) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	6
Jackup [Member] | North & South America (Excl. Brazil) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	15
Other [Member] | North & South America (Excl. Brazil) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs
North & South America (Excl. Brazil) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	21	[1]
Deepwater [Member] | Brazil [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	6
Midwater [Member] | Brazil [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	5
Other [Member] | Brazil [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs
Brazil [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	11	[1]
Deepwater [Member] | Europe & Mediterranean [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	1
Jackup [Member] | Europe & Mediterranean [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	9
Other [Member] | Europe & Mediterranean [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs
Europe & Mediterranean [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	10	[1]
Deepwater [Member] | Middle East & Africa [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	3
Midwater [Member] | Middle East & Africa [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	1
Jackup [Member] | Middle East & Africa [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	12
Other [Member] | Middle East & Africa [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs
Middle East & Africa [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	16	[1]
Deepwater [Member] | Asia & Pacific Rim [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	1
Jackup [Member] | Asia & Pacific Rim [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	10
Other [Member] | Asia & Pacific Rim [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	1
Asia & Pacific Rim [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	12	[1]
Deepwater [Member] | Asia & Pacific Rim (under construction) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	4
Jackup [Member] | Asia & Pacific Rim (under construction) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	2
Other [Member] | Asia & Pacific Rim (under construction) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs
Asia & Pacific Rim (under construction) [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	6	[1]
Deepwater [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	21
Midwater [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	6
Jackup [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	48
Other [Member]
Segment Reporting Information [Line Items]
Total Number Of Contract Drilling Rigs	1
[1] We have two deepwater drilling management contracts not included in the table above. In October 2011, we entered into an agreement with Keppel FELS Limited to construct an ultra-high specification harsh environment jackup rig, which is not included in the table above.

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Total Number Of Contract Drilling Rigs

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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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