The amount of interest that has been capitalized associated with unproved properties (excluded from amortization).

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- Definition

Total cost of oil and gas properties subject to amortization per the full cost method of accounting.

+ References

No definition available.

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- Definition

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.

+ 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))

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- Definition

Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61901-109447

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- Definition

Capitalized costs of unproven properties that include fee ownership or a lease, concession, or other interest representing the right to extract oil or gas subject to such terms as may be imposed by the conveyance of that interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61926-109447

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61901-109447

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Properties

-URI http://asc.fasb.org/extlink&oid=21914647

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-Glossary Unproved Properties

-URI http://asc.fasb.org/extlink&oid=6527831

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- Definition

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.

+ References

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- Definition

The sum of capitalized costs relating to oil and gas producing activities before accounting for accumulated depreciation.

+ References

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- Definition

Net amount of capitalized costs relating to oil and gas producing activities.

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- Definition

The capitalized costs incurred (excluded from amortization), as of the date of the balance sheet, to obtain access to proved reserves and to provide facilities for extracting, treating, gathering and storing the oil and gas.

+ References

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- Definition

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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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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- Definition

Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

The cumulative amount of depreciation (related to capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy) that has been recognized in the income statement.

+ References

No definition available.

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The net amount of capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy.

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No definition available.

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Oil and Gas Assets (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Oil and gas properties:
Subject to amortization	$ 14,478		$ 15,107
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	1,398		1,300
Gross oil and gas properties	15,876		16,407
Capitalized Costs, Accumulated Depreciation, Depletion, Amortization and Valuation Allowance for Relating to Oil and Gas Producing Activities	(7,691)		(8,306)
Net oil and gas properties	8,185		8,101
Accumulated depreciation and amortization	(78)		(69)
Net other property and equipment	180		174
Cost of oil and gas properties not subject to amortization
Acquisition costs	809
Exploration costs	329
Development costs	71
Fee mineral interests	24
Capitalized interest	165
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	1,398		1,300
Oil and Gas Assets (Textuals) [Abstract]
Proceeds from Sale of Oil and Gas Property and Equipment	12	19
Furniture and Fixtures [Member]
Oil and gas properties:
Other property and equipment	149		139
Gas Gathering and Processing Equipment [Member]
Oil and gas properties:
Other property and equipment	109		104
Costs incurred in 2014 not subject to amortization [Member]
Oil and gas properties:
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	427
Cost of oil and gas properties not subject to amortization
Acquisition costs	84
Exploration costs	301
Development costs	16
Fee mineral interests	0
Capitalized interest	26
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	427
Costs incurred in 2013 not subject to amortization [Member]
Oil and gas properties:
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	280
Cost of oil and gas properties not subject to amortization
Acquisition costs	199
Exploration costs	19
Development costs	8
Fee mineral interests	1
Capitalized interest	53
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	280
Costs incurred in 2012 not subject to amortization [Member]
Oil and gas properties:
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	196
Cost of oil and gas properties not subject to amortization
Acquisition costs	96
Exploration costs	2
Development costs	31
Fee mineral interests	0
Capitalized interest	67
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	196
Costs incurred in 2011 and prior not subject to amortization [Member]
Oil and gas properties:
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	495
Cost of oil and gas properties not subject to amortization
Acquisition costs	430
Exploration costs	7
Development costs	16
Fee mineral interests	23
Capitalized interest	19
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative	$ 495