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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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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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 shares issued or sold by the subsidiary or equity method investee per stock transaction.

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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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The percentage of ownership of common stock or equity participation in a business contributed to a consolidated master limited partnership.

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General, Description of Business, and Basis of Presentation (Details) (USD $) In Millions, except Share data, unless otherwise specified			9 Months Ended	3 Months Ended			9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 General and Limited Partner [Member]	Sep. 30, 2013 Williams Partners L.P.	Mar. 31, 2013 Williams Partners L.P.	Mar. 31, 2013 Williams Partners L.P. Private Placement [Member]	Sep. 30, 2013 Constitution Pipeline Company LLC [Member]	Sep. 30, 2013 Bluegrass Pipeline Company LLC [Member]	Sep. 30, 2013 Geismar [Member]	Sep. 30, 2013 Gulfstream Natural Gas System, L.L.C.[Member]	Sep. 30, 2013 Access Midstream Partners, GP, L.L.C.[Member]	Sep. 30, 2013 Access Midstream Partners Lp [Member]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Goodwill	$ 646	$ 649
Other intangibles	$ 1,659	$ 1,704
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage										50.00%	50.00%	23.00%
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Variable Interest Entity Ownership Percentage							41.00%	50.00%
Sale Of Stock Number Of Shares Issued In Transaction				24,725,000	15,937,500	3,000,000
Master limited partnership, ownership percentage			64.00%
Percent Ownership Of Contributed Business									83.30%