Cash Paid for Interest (Net of Amounts Capitalized) and Income Taxes, as well as Non-Cash Transactions Table (Detail) (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Cash paid:
Interest	$ 708	$ 579
Income taxes	238	209
Non-cash investing activities:
Fair value of properties and equipment received in non-cash exchange transactions	4	32
Wattenberg Natural-Gas Processing Plant [Member]
Business Acquisition [Line Items]
Gain related to the fair-value remeasurement of Anadarko's pre-acquisition 7% equity interest in the Wattenberg Plant	$ 21

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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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In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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