Cost incurred related to the gas activities, such as transportation, marketing and processing crude oil, natural gas and refined petroleum products.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62136-109447

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

The loss recognized on termination of a contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 275
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84167019&loc=d3e54681-109401

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No definition available.

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- Definition

The excess of unamortized costs capitalized within a cost center, less related deferred income taxes, over the cost center ceiling limitation, which is charged to expense for oil and gas producing companies that use full cost method of accounting for investments in oil and gas producing 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)(4)(ii))
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Impairments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Impairments - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Property, Plant and Equipment [Line Items]
Impairment of oil and natural gas properties	$ 0	$ 1,070	$ 0	$ 2,067
Loss on Transportation Agreement	1,027	$ 1,207	2,355	$ 2,149
Transportation Equipment [Member] \| Natural Gas [Member]
Property, Plant and Equipment [Line Items]
Loss on Contract Termination	$ 23		126
Transportation Equipment [Member] \| Oil [Member]
Property, Plant and Equipment [Line Items]
Loss on Transportation Agreement			$ 290