SUPPLEMENTARY OIL AND GAS INFORMATION (UNAUDITED) (Schedule of Costs Not Subject to Amortization) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Capitalized Costs of Unproved Properties Excluded from Amortization, Period Cost	$ 2,021,000,000	$ 8,066,000,000
Total	10,087,000,000
Costs Not Subject to Amortization to be Transferred, Percentage	48.00%
Majority of Costs Not Subject to Amortization to be Transferred, Period	5 years
Net Undeveloped Acreage Covered by Expiring Leases, Percentage	35.00%
Haynesville [Member]
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Acreage Held by Production or Held by Operations, Percentage	95.00%
Onshore [Member] \| U.S. [Member]
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Acquisition costs	2,303,000,000
Acquisition Costs, Period Cost	18,000,000	2,285,000,000
Exploration costs	121,000,000
Exploration Costs, Period Cost	119,000,000	2,000,000
Capitalized interest	27,000,000
Capitalized Costs of Unproved Properties Excluded from Amortization, Period Cost	22,000,000	5,000,000
Offshore [Member] \| U.S. [Member]
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Acquisition costs	7,094,000,000
Acquisition Costs, Period Cost	1,413,000,000	5,681,000,000
Exploration costs	429,000,000
Exploration Costs, Period Cost	387,000,000	42,000,000
Capitalized interest	75,000,000
Capitalized Costs of Unproved Properties Excluded from Amortization, Period Cost	39,000,000	36,000,000
Offshore [Member] \| International [Member]
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Acquisition costs	15,000,000
Acquisition Costs, Period Cost	0	15,000,000
Exploration costs	23,000,000
Exploration Costs, Period Cost	23,000,000	0
Capitalized interest	0
Capitalized Costs of Unproved Properties Excluded from Amortization, Period Cost	$ 0	$ 0
Minimum [Member]
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Remainder of Costs Not Subject to Amortization to be Transferred, Period	7 years
Maximum [Member]
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]
Remainder of Costs Not Subject to Amortization to be Transferred, Period	10 years

The percentage of acreage held by production.

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The capitalized interest incurred for undeveloped acreage and wells in progress pending determination, cumulative total.

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The percentage of costs not subject to amortization that will be transferred to the amortization base over a specific period of time.

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The period during which most of costs not subject to amortization that will be transferred to the amortization base.

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The percentage of total net undeveloped acreage covered by expiring leases through the end of a specified period.

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No definition available.

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The period during which the remainder of costs not subject to amortization that will be transferred to the amortization base.

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The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-10.(c)(7)(ii))

-URI http://asc.fasb.org/extlink&oid=27015464&loc=d3e511914-122862

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 10

-Paragraph c

-Subparagraph 3(ii)(A)

-Article 4

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The capitalized costs incurred (excluded from amortization), as of the date of the balance sheet, to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

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The sum of the capitalized costs incurred during the period of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

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The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

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The capitalized costs incurred during the period (excluded from amortization) in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. Exploration costs also include costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, the maintenance of land and lease records, dry hole contributions and bottom hole contributions, costs of drilling and equipping exploratory wells and costs of drilling exploratory-type stratigraphic test wells.

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The capitalized costs incurred (excluded from amortization), as of the date of the balance sheet, in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. Exploration costs also include costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, the maintenance of land and lease records, dry hole contributions and bottom hole contributions, costs of drilling and equipping exploratory wells and costs of drilling exploratory-type stratigraphic test wells.

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