Dispositions Dispositions 2 (Details) (Angola Blk 31 [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2013
Angola Blk 31 [Member]
Long Lived Assets Held-for-sale [Line Items]
Disposal Group, Including Discontinued Operation, Other Current Assets	$ 15
Disposal Group, Including Discontinued Operation, Other Noncurrent Assets	1,598
Assets Held-for-sale, at Carrying Value	1,613
Liabilities of Disposal Group, Including Discontinued Operation, Current	42
Liabilities of Disposal Group, Including Discontinued Operation, Noncurrent	41
Liabilities of Disposal Group, Including Discontinued Operation	$ 83

Represents the sum of the carrying value of all the Assets Held-for-Sale at the balance sheet date.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount of assets not otherwise specified in the taxonomy that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

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- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount as of the balance sheet date of assets not otherwise specified, and which are expected to be realized or consumed after one year or beyond the normal operating cycle, if longer. For an unclassified balance sheet, represents both current and noncurrent other assets.

+ References

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- Definition

The obligations arising from the sale, disposal, or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

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- Definition

Carrying value as of the balance sheet date of current obligations (due less than one year or one operating cycle, if longer) arising from the sale, disposal or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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- Definition

Carrying value of noncurrent obligations (due more than one year or one operating cycle, whichever is longer) relating to the sale, disposal or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation), as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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