Transactions with Affiliates Related Party Transations (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) employee	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Advances from affiliate	$ 316,900		$ 252,500
Related party transaction, rate	0.27%
Entity number of employees \| employee	0
Expenses, related party	$ 86,900	$ 92,200
Equity distributions to parent	270,000	176,000
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Operating revenues, related party	2,600	3,300
Cost of natural gas sales, related party	2,500	1,600
Expenses, related party	$ (1,000)	$ (1,200)

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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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-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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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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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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