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Capitalized Internal Costs Related To Acquisitions Exploration And Development in Subsidiaries

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- Definition

Value of qualifying cash flow hedges used in calculating the ceiling limitation, which represents the best measure of estimated cash flows from future production of affected oil and gas reserves, as disclosed in the financial statement footnotes.

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- Definition

Discount Rate Of Natural Gas, Oil and Natural Gas Liquid Reserves

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Duration Average Quoted Price Including Impact Of Derivatives Calculate Ceiling Value Of Reserves

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Price used in the full cost ceiling test. Prior to the fourth quarter of 2009, this price was the quoted market price as of the balance sheet date (if the quoted price at the balance sheet date resulted in an impairment, management could previously use a more favorable quoted market price at a day subsequent to the balance sheet date but prior to the auditor's report on the affected financial statements). For all periods including and subsequent to the fourth quarter of 2009, this price is an average of the prices for the first-day-of-the-month during the previous 12 months.

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Natural Gas and Oil Properties [Line Items]

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Number Of Locations

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- Definition

Percentage of Present Worth of Proved Reserves

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Present Value of Proved Reserves, Discounted Basis

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No definition available.

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The net increase (decrease) in production of quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable.

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No definition available.

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- Definition

Proved Reserve (Volume), Dispositions

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No definition available.

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Proved Reserves, Committed Development Period

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Proved Reserves Production Volumes Replaced With Reserves Additions, Percentage

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The average market prices for sales of oil and gas used in oil and gas reserve estimation and disclosure.

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Area of land held.

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No definition available.

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- Definition

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.

+ 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=50486907&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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- Definition

Amount of interest capitalized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Allowance for Funds Used during Construction
-URI http://asc.fasb.org/extlink&oid=6504829

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-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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- Definition

Additions to proved reserves that result from (1) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (2) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 5
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61831-109447

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The net quantity of proved reserves as of the balance sheet date. Proved oil reserves are the estimated quantities of crude oil and natural gas liquids which geological and engineering data demonstrate with reasonable certainty to be recoverable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 235
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=50486907&loc=d3e511914-122862

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Production of proved reserves.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 5
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61831-109447

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Revisions represent changes in previous estimates of proved reserves, either upward or downward, resulting from new information (except for an increase in proved acreage) normally obtained from development drilling and production history or resulting from change in economic factors.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61831-109447

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Net quantities of an enterprise's interests in proved undeveloped reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other renewable natural resource that is intended to be upgraded into synthetic oil and gas as of the beginning and the end of the year. "Net" quantities of reserves include those relating to the enterprise's operating and nonoperating interests in properties. Quantities of reserves relating to royalty interests owned are included in "net" quantities if the necessary information is available to the enterprise. "Net" quantities does not include reserves relating to interests of others in properties owned by the enterprise. The unit of measure for reserve quantities is defined as "barrels" for oil and synthetic oil reserves or "cubic feet" or "cubic meters" for natural gas and synthetic gas reserves.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 932
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-URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e61797-109447

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Natural Gas And Oil Producing Activities (Narrative) (Details) ft³ in Thousands, $ in Millions	12 Months Ended				108 Months Ended	144 Months Ended
	Dec. 31, 2015 USD ($) $ / bbl $ / MMBTU site MBbls ft³	Dec. 31, 2014 USD ($) a $ / bbl $ / MMBTU site MBbls ft³	Dec. 31, 2013 USD ($) $ / bbl $ / MMBTU site MBbls ft³	Dec. 31, 2012 MBbls ft³	Dec. 31, 2012 USD ($) MBbls ft³	Dec. 31, 2015 USD ($) site MBbls ft³	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)
Natural Gas and Oil Properties [Line Items]
Natural gas, oil and NGL reserves discount	10.00%	10.00%	10.00%
Period of time needed to calculate ceiling value of reserves	12 months	12 months	12 months
Cash flow hedges impact on ceiling value, net of tax \| $							$ 40	$ 60
Net unevaluated costs excluded from amortization \| $	$ 522	$ 2,948	$ 82		$ 175	$ 3,727
Percentage of present worth of proved reserves evaluated in audit	100.00%	97.00%	95.00%
Capitalized interest based on weighted average cost of borrowings \| $	$ 204	$ 55	$ 62
Capitalized internal costs related to acquisition, exploration and development \| $	307	320	264
Capitalized internal costs related to acquisition, exploration and development activities - subsidiaries \| $	$ 118	$ 123	$ 103
Production		768,000,000	657,000,000	565,000,000
Production volumes replaced with proved reserve additions, net upward revisions and acquisitions, percentage		591.00%	550.00%
Extensions, discoveries and other additions	592,000,000	1,693,000,000	3,285,000,000
Revisions	(4,083,000,000)	543,000,000
Proved reserves, dispositions	179,000,000					179,000,000
Undeveloped Properties Fayetteville Shale [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	34,000,000	573,000,000	1,530,000,000
Undeveloped Properties Marcellus Shale [Member]
Natural Gas and Oil Properties [Line Items]
Net unevaluated costs excluded from amortization \| $	$ 121
Undeveloped Properties New Ventures - Excluding Canada [Member]
Natural Gas and Oil Properties [Line Items]
Net unevaluated costs excluded from amortization \| $	265
Exploration Program in Canada [Member]
Natural Gas and Oil Properties [Line Items]
Net unevaluated costs excluded from amortization \| $	50
Wells In Progress [Member]
Natural Gas and Oil Properties [Line Items]
Net unevaluated costs excluded from amortization \| $	$ 157
Southwest Appalachia [Member]
Natural Gas and Oil Properties [Line Items]
Net increase (decrease) in production	140,000,000	3,000,000				140,000,000
Northeast Appalachia [Member]
Natural Gas and Oil Properties [Line Items]
Net increase (decrease) in production	106,000,000	103,000,000	97,000,000			106,000,000
Northeast Appalachia [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions		636,000,000	62,000,000
Northeast Appalachia [Member] \| Higher Gas Prices [Member]
Natural Gas and Oil Properties [Line Items]
Revisions		10,000,000	35,000,000
Fayetteville Shale [Member]
Natural Gas and Oil Properties [Line Items]
Net increase (decrease) in production	(29,000,000)	8,000,000	1,000,000			(29,000,000)
Fayetteville Shale [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions		(126,000,000)	16,000,000
Fayetteville Shale [Member] \| Higher Gas Prices [Member]
Natural Gas and Oil Properties [Line Items]
Revisions		38,000,000	191,000,000
Other Properties [Member]
Natural Gas and Oil Properties [Line Items]
Net increase (decrease) in production	(9,000,000)					(9,000,000)
Acquisitions [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	114,000,000	2,304,000,000	4,000,000
Developed Properties Northeast Appalachia [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	202,000,000	246,000,000	386,000,000
Developed Properties Northeast Appalachia [Member] \| Lower Gas Prices [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	(2,315,000,000)
Developed Properties Northeast Appalachia [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	1,383,000,000
Developed Properties Southwest Appalachia [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	84,000,000
Developed Properties Southwest Appalachia [Member] \| Lower Gas Prices [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	(1,875,000,000)
Developed Properties Southwest Appalachia [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	209,000,000
Developed Properties Fayetteville Shale [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	129,000,000	283,000,000	557,000,000
Developed Properties Fayetteville Shale [Member] \| Lower Gas Prices [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	(1,496,000,000)
Developed Properties Fayetteville Shale [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	10,000,000
Developed Properties Other Divisions [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	1,000,000
Developed Properties Other Divisions [Member] \| Lower Gas Prices [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	(32,000,000)
Developed Properties Other Divisions [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions	33,000,000
Undeveloped Properties Northeast Appalachia [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	138,000,000	589,000,000	810,000,000
Undeveloped Properties Southwest Appalachia [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions	4,000,000
East Texas and Arkoma Basin [Member]
Natural Gas and Oil Properties [Line Items]
Net increase (decrease) in production		(3,000,000)	(7,000,000)
Developed Properties Brown Dense [Member]
Natural Gas and Oil Properties [Line Items]
Extensions, discoveries and other additions		2,000,000	2,000,000
Ark-La-Tex [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions		(21,000,000)
Ark-La-Tex [Member] \| Higher Gas Prices [Member]
Natural Gas and Oil Properties [Line Items]
Revisions		6,000,000	21,000,000
Undeveloped Properties, Various Locations [Member]
Natural Gas and Oil Properties [Line Items]
Natural gas, oil and NGL reserves discount	10.00%	10.00%	10.00%
Proved undeveloped reserves	217,000,000	181,000,000	662,000,000			217,000,000
Number of locations \| site	75	60	268			75
Present value of proved reserves, discounted basis \| $	$ (34)	$ (28)	$ (97)			$ (34)
Proved reserves, committed development period	5 years
New Ventures [Member]
Natural Gas and Oil Properties [Line Items]
Net increase (decrease) in production			1,000,000
New Ventures [Member] \| Performance [Member]
Natural Gas and Oil Properties [Line Items]
Revisions			1,000,000
Chesapeake Property Acquisition [Member]
Natural Gas and Oil Properties [Line Items]
Net unevaluated costs excluded from amortization \| $	$ 2,900
Area of land purchased \| a		413,000
Natural Gas [Member]
Natural Gas and Oil Properties [Line Items]
Proved developed and undeveloped reserves	5,917,000,000	9,809,000,000	6,974,000,000	4,017,000,000	4,017,000,000	5,917,000,000
Production	899,000,000	766,000,000	656,000,000
Extensions, discoveries and other additions	546,000,000	1,692,000,000	3,284,000,000
Revisions	(3,458,000,000)	542,000,000	325,000,000
Proved undeveloped reserves	443,000,000	4,134,000,000	2,737,000,000	821,000,000	821,000,000	443,000,000
Average market prices used in reserves \| $ / MMBTU	2.59	4.35	3.67
Oil [Member]
Natural Gas and Oil Properties [Line Items]
Proved developed and undeveloped reserves \| MBbls	8,753	37,615	373	244	244	8,753
Production \| MBbls	2,265	235	138
Extensions, discoveries and other additions \| MBbls	1,367	250	229
Revisions \| MBbls	(28,394)	(14)	38
Proved undeveloped reserves \| MBbls		30,170	1	1	1
Average market prices used in reserves \| $ / bbl	46.79	91.48	93.42
NGL [Member]
Natural Gas and Oil Properties [Line Items]
Full cost ceiling test, price \| $ / bbl	6.82	23.79	43.45
Proved developed and undeveloped reserves \| MBbls	40,947	118,699				40,947
Production \| MBbls	10,702	231	50
Extensions, discoveries and other additions \| MBbls	6,274	48
Revisions \| MBbls	(75,664)	66	50
Proved undeveloped reserves \| MBbls		80,067
Average market prices used in reserves \| $ / MMBTU	6.82	23.79	43.45
Natural Gas and Oil [Member]
Natural Gas and Oil Properties [Line Items]
Production	976,000,000	768,000,000
Natural Gas and Oil [Member] \| Estimated [Member]
Natural Gas and Oil Properties [Line Items]
Proved developed and undeveloped reserves	6,215,000,000	10,747,000,000	6,976,000,000	4,018,000,000	4,018,000,000	6,215,000,000
Synthetic Gas, Synthetic Oil or Nonrenewable Natural Resources [Member]
Natural Gas and Oil Properties [Line Items]
Proved developed and undeveloped reserves	0					0