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

Money Pool Borrowings

+ References

No definition available.

+ Details

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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

+ Details

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- 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=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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- Details

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- Details

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Related Party Transactions and Major Customers (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Related Party Transaction [Line Items]
Investments (borrows) in Money Pool	$ 107cehe_InvestmentsInMoneyPool								$ 107cehe_InvestmentsInMoneyPool
Money Pool Borrowings					(3)cehe_MoneyPoolBorrowings					(3)cehe_MoneyPoolBorrowings
Interest Income (Expense) Net, Related Party									(1)	20	19
Corporate service charges									159	147	143
Proceeds from Contributions from Parent									90	0	0
Revenues	679us-gaap_Revenues	839us-gaap_Revenues	698us-gaap_Revenues	630us-gaap_Revenues	644us-gaap_Revenues	745us-gaap_Revenues	656us-gaap_Revenues	532us-gaap_Revenues	2,846us-gaap_Revenues	2,577us-gaap_Revenues	2,540us-gaap_Revenues
Affiliates of NRG Energy, Inc. [Member]
Related Party Transaction [Line Items]
Revenues									735	658	648
Affiliates of Energy Future Holdings Corp. [Member]
Related Party Transaction [Line Items]
Revenues									$ 189	$ 167	$ 162