The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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-Publisher FASB
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The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

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The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Maximum Reduction Of Quarterly Incentive Distributions

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General, Description of Business, and Basis of Presentation (Details) - USD ($) $ in Millions		1 Months Ended				3 Months Ended		9 Months Ended
	Sep. 28, 2015	Aug. 31, 2016	May 31, 2016	Feb. 29, 2016	Nov. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Equity Method Investments						$ 7,084		$ 7,084		$ 7,336
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Parent, general partner ownership percentage						2.00%	2.00%	2.00%	2.00%
WPZ Merger Public Unit Exchange [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Termination Fee	$ 428
Maximum Reduction Of Quarterly Incentive Distributions	$ 209
Reduction in incentive distribution rights payment			$ 10	$ 209	$ 209
Delaware Basin Gas Gathering System [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments						$ 964		$ 964
Central [Member] \| Delaware Basin Gas Gathering System [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						50.00%		50.00%
Northeast G And P [Member] \| Appalachia Midstream Services, LLC [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Subsidiary, ownership percentage								45.00%
Northeast G And P [Member] \| Utica East Ohio Midstream, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						62.00%		62.00%
Northeast G And P [Member] \| Laurel Mountain Midstream, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						69.00%		69.00%
Northeast G And P [Member] \| Caiman Energy II, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						58.00%		58.00%
Atlantic Gulf [Member] \| Gulfstar One [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Variable Interest Entity Ownership Percentage								51.00%
Atlantic Gulf [Member] \| Constitution Pipeline Company LLC [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Variable Interest Entity Ownership Percentage								41.00%
Atlantic Gulf [Member] \| Gulfstream Natural Gas System, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						50.00%		50.00%
Atlantic Gulf [Member] \| Discovery Producer Services LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						60.00%		60.00%
NGL And Petchem Services [Member] \| Geismar [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Subsidiary, ownership percentage								88.50%
NGL And Petchem Services [Member] \| Conway Fractionator [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Subsidiary, ownership percentage								50.00%
NGL And Petchem Services [Member] \| Overland Pass Pipeline Company LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						50.00%		50.00%
Limited Partner [Member] \| The Williams Companies, Inc. [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Parent, limited partner ownership percentage								58.00%
General Partner [Member] \| The Williams Companies, Inc. [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Parent, general partner ownership percentage		2.00%						2.00%