Number of persons employed by the Entity

No definition available.

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- Definition

Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due within 1 year (or 1 business cycle).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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 210.5-02.3(a)(2))

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Related Parties

-URI http://asc.fasb.org/extlink&oid=16382449

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(k)(1))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

The distributions of earnings to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Details

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- Details

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Transactions with Affiliates (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
Transactions with Affiliates (Details) $ in Thousands	Oct. 31, 2015 USD ($)	Sep. 30, 2015 USD ($) employee	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) employee	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Related Party Transaction [Line Items]
Advances to affiliate		$ 187,358		$ 187,358		$ 135,054
Related party transaction, rate				0.01%
Entity number of employees \| employee		0		0
Related party transaction, expenses from transactions with related party		$ 24,100	$ 24,400	$ 74,500	$ 74,800
Cash distributions to parent				129,000	$ 191,000
Williams Partners L.P. [Member]
Related Party Transaction [Line Items]
Advances to affiliate		$ 187,400		$ 187,400		$ 135,100
Subsequent Event [Member]
Related Party Transaction [Line Items]
Cash distributions to parent	$ 39,000