Percentage of voting equity interests acquired at the acquisition date in the business combination.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Subsequent Events (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		0 Months Ended	1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Apr. 15, 2015	Apr. 30, 2015	Apr. 06, 2015
Subsequent Event [Line Items]
Payments to Acquire Equity Method Investments	$ 83	$ 228
5.875% Senior Unsecured Notes due 2021 [Member] \| Williams Partners L.P. [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Long-term debt retired			750
Long-term debt interest rate			5.875%
Utica East Ohio Midstream, LLC [Member]
Subsequent Event [Line Items]
Equity Method Investment, Ownership Percentage	49.00%
Utica East Ohio Midstream, LLC [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Payments to Acquire Equity Method Investments				$ 575
Utica East Ohio Midstream, LLC [Member] \| Subsequent Event [Member] \| Percentage To Be Acquired By Us Without Participation By Another [Member]
Subsequent Event [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired					21.00%
Utica East Ohio Midstream, LLC [Member] \| Subsequent Event [Member] \| Percentage To Be Acquired By Us With Participation By Another [Member]
Subsequent Event [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired					13.00%
Utica East Ohio Midstream, LLC [Member] \| Subsequent Event [Member] \| Percentage To Be Acquired By Another If Participation Right Is Exercised [Member]
Subsequent Event [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired					8.00%