The minimum threshold of the aggregate value received by the third party related to current and/or future claims.

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- Definition

Insurance coverage for potential financial losses.

+ Details

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- Definition

Amount of risk retained by the entity before the insurance arrangement begins to provide coverage for potential financial losses.

+ Details

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- Definition

Potential net insurance recoveries

+ Details

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- Definition

The percentage of the aggregate value received by third party.

+ Details

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- Definition

The amount or range of possible amounts of gain that could be realized upon the resolution of a contingency.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 30

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6397426&loc=d3e17499-108355

+ Details

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- Definition

Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ Details

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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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Deepwater Horizon Events - Insurance and Other Recoveries (Detail) (USD $)	Sep. 30, 2011 Deepwater Horizon [Member]	Sep. 30, 2011 Deepwater Horizon [Member] Non-Operated Leasehold Interest, 25 Percent [Member] Operating Agreement [Member] Minimum [Member]	Apr. 19, 2010 Deepwater Horizon [Member] Non-Operated Leasehold Interest, 25 Percent [Member] Maximum [Member]	Oct. 16, 2011 Deepwater Horizon [Member] BP Exploration and Production Inc. [Member] BP Settlement Agreement [Member]	Oct. 16, 2011 Deepwater Horizon [Member] Maximum [Member] BP Settlement Agreement [Member]	Apr. 19, 2010 Maximum [Member]
Loss Contingencies [Line Items]
Insurance coverage for potential financial losses			$ 178,000,000			$ 710,000,000
Insurance coverage for potential financial losses, deductibles			15,000,000			60,000,000
Receivable for any potential insurance recoveries related to the Deepwater Horizon Events	0
Potential net insurance recoveries		163,000,000
Gain contingency, unrecorded amount					1,000,000,000
Third party receivable from future claims percentage				12.50%
Minimum threshold required from future claims for third party receivable				$ 1,500,000,000