Number of persons employed by the Entity

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- Definition

Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle).

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- Definition

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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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- Definition

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

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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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- 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.

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

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- Definition

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

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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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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Transactions with Affiliates Related Party Transations (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2019 USD ($)	Sep. 30, 2019 USD ($) employee	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) employee	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Related Party Transaction [Line Items]
Advances from affiliates		$ 169,908		$ 169,908		$ 0
Advances to affiliate		$ 0		$ 0		$ 33,034
Related party transaction, rate				1.92%
Entity number of employees \| employee		0		0
Expenses, related party		$ 110,700	$ 99,200	$ 315,400	$ 290,000
Severance accrual				27,000
Equity distributions to parent				559,000	290,000
Cash contributions from parent				0	340,000
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Operating revenues, related party		2,800	2,900	8,400	6,200
Cost of natural gas sales, related party		800	1,200	3,000	4,900
Expenses, related party		(1,200)	$ (1,700)	(3,500)	$ (3,900)
Williams Companies Inc [Member]
Related Party Transaction [Line Items]
Advances to affiliate		$ 33,000		$ 33,000
Subsequent Event [Member]
Related Party Transaction [Line Items]
Equity distributions to parent	$ 265,000