Number of persons employed by the Entity

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- Definition

Duration Of Period For Deferred Revenue Recognition

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No definition available.

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- Definition

Noncash distribution to Parent- The noncash distribution of earnings to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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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).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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-Subparagraph (SX 210.5-02.3(a)(2))
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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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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- Definition

The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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- Definition

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

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 1
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- 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.

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- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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-Publisher FASB
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-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
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Transactions with Affiliates Related Party Transations (Details) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Oct. 31, 2018 USD ($)	Jul. 31, 2017 USD ($)	Sep. 30, 2018 USD ($) employee	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) employee	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Related Party Transaction [Line Items]
Advances to affiliate			$ 244,816		$ 244,816		$ 395,247
Related party transaction, rate					1.99%
Entity number of employees \| employee			0		0
Expenses, related party			$ 99,200	$ 91,400	$ 290,000	$ 261,100
Cash distributions to parent					290,000	330,000
Cash contributions from parent					340,000	110,000
Noncash distribution to Parent		$ 240,000
Duration Of Period For Deferred Revenue Recognition		25 years
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Operating revenues, related party			2,900	2,500	6,200	8,900
Cost of natural gas sales, related party			1,200	1,000	4,900	2,900
Expenses, related party			(1,700)	$ (900)	(3,900)	$ (2,700)
Williams Companies Inc [Member]
Related Party Transaction [Line Items]
Advances to affiliate			$ 244,800		$ 244,800
Williams Partners L. P. [Member]
Related Party Transaction [Line Items]
Advances to affiliate							$ 395,200
Subsequent Event [Member]
Related Party Transaction [Line Items]
Cash distributions to parent	$ 200,000