Net interest income (expense) related to affiliate investments or borrowings

No definition available.

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- Definition

Investments in Money Pool

+ References

No definition available.

+ Details

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- Definition

Weighted average interest rate of outstanding investments in money pool.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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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.

+ Details

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- Definition

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

+ References

No definition available.

+ Details

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- Definition

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Related Party Transactions and Major Customers (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Related Party Transaction [Line Items]
Investments in money pool	$ 67		$ 67		$ 96
Affiliate related net interest income (expense)	0	$ (1)	1	$ (4)
Revenues from major customers	843	909	2,233	2,328
Affiliates of NRG Energy, Inc. [Member]
Related Party Transaction [Line Items]
Revenues from major customers	221	223	540	527
Affiliates of Vistra Energy Corp. [Member]
Related Party Transaction [Line Items]
Revenues from major customers	72	71	172	166
Operation And Maintenance Expense [Member] \| CenterPoint Energy [Member]
Related Party Transaction [Line Items]
Corporate service charges	41	43	127	131
Operation And Maintenance Expense [Member] \| CERC Corp [Member]
Related Party Transaction [Line Items]
Corporate service charges	2	2	5	5
Other revenues from transactions with related party	$ (3)	$ (4)	$ (11)	$ (11)
Investments [Member]
Related Party Transaction [Line Items]
Weighted average interest rate of money pool investments	1.44%		1.44%