v2.4.0.6

Assets Held for Sale or Sold (Details) (Cedar Creek Anticline [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Cedar Creek Anticline [Member]
Assets Held for Sale (Textual) [Abstract]
Proceeds of asset disposition	$ 989
Gain (Loss) on Sale of Oil and Gas Property	(62)
Net carrying value	1,051
Amount of PP&E in carrying value of asset	1,079
Amount of asset retirement obligations in carrying value of asset	$ 28

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Long-lived assets that are held for sale apart from normal operations and anticipated to be sold in less than one year.

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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.

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For the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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Gain (loss) recorded from sale of oil and gas properties, includes the realized gains (losses) on the sale of proved and unproved oil and gas properties.

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The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

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