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No definition available.

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The increase during the period in capital lease obligations due to entering into new capital leases.

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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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Supplemental Cash Flow Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Capital Lease Obligation [Member]	Dec. 31, 2011 Wattenberg Natural-Gas Processing Plant [Member]	May 31, 2011 Wattenberg Natural-Gas Processing Plant [Member]
Cash paid (received)
Interest	$ 684	$ 806	$ 672
Income taxes	(300)	262	308
Non-cash investing activities
Fair value of properties and equipment received in non-cash exchange transactions	65	19	37
Business Acquisition [Line Items]
Gain related to the fair-value remeasurement of Anadarko's pre-acquisition 7% equity interest in the Wattenberg Plant					21
Business combination, equity interest in acquiree, percentage						7.00%
Other Significant Noncash Transactions [Line Items]
Capital lease obligation				(118)
Capital lease obligation			$ 226