Related-Party Transactions (Narrative) (Details) (USD $) In Millions, unless otherwise specified			1 Months Ended	9 Months Ended						3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended					9 Months Ended						3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Jul. 31, 2014 Energy Future Holdings Corp. [Member] Other Postretirement Benefit Plan [Member]	Sep. 30, 2013 Oncor [Member] Internal Revenue Service (IRS) [Member] Audit Years 1997 Through 2002 [Member]	Sep. 30, 2014 Payable Attributable To Income Taxes [Member] Energy Future Holdings Corp. [Member] Internal Revenue Service (IRS) [Member]	Dec. 31, 2013 Payable Attributable To Income Taxes [Member] Energy Future Holdings Corp. [Member] State and Local Jurisdiction [Member]	Sep. 30, 2014 Payable Attributable To Income Taxes [Member] Oncor [Member] State and Local Jurisdiction [Member]	Sep. 30, 2014 Payable Attributable To Income Taxes [Member] Oncor Holdings [Member]	Dec. 31, 2013 Receivable attributable to income taxes [Member] Energy Future Holdings Corp. [Member] Internal Revenue Service (IRS) [Member]	Sep. 30, 2014 Energy Future Intermediate Holding CO LLC [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Energy Future Intermediate Holding CO LLC [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Energy Future Intermediate Holding CO LLC [Member] Sponsor Fees Allocated [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Sponsor Fees Allocated [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Energy Future Intermediate Holding CO LLC [Member] Sponsor Fees Allocated [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Sponsor Fees Allocated [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Energy Future Intermediate Holding CO LLC [Member] Legal And Consulting Fees [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Legal And Consulting Fees [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Energy Future Intermediate Holding CO LLC [Member] Legal And Consulting Fees [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Legal And Consulting Fees [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Energy Future Intermediate Holding CO LLC [Member] Income tax payments [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Income tax payments [Member] Energy Future Holdings Corp. [Member]	Dec. 31, 2012 Energy Future Intermediate Holding CO LLC [Member] TCEH to EFH [Member] Line of Credit [Member] Indirect Guarantee of Indebtedness [Member]	Sep. 30, 2013 Energy Future Intermediate Holding CO LLC [Member] Oncor [Member] Texas Comptroller Of Public Accounts [Member] Audit Years 1997 Through 2001 [Member]	Sep. 30, 2014 Oncor Holdings [Member] Oncor [Member]	Sep. 30, 2013 Oncor Holdings [Member] Oncor [Member]	Sep. 30, 2014 Oncor Holdings [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Oncor Holdings [Member] Energy Future Holdings Corp. [Member]	Dec. 31, 2013 Oncor Holdings [Member] Payable Attributable To Income Taxes [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Oncor [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Oncor [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Oncor [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2013 Oncor [Member] Energy Future Holdings Corp. [Member]	Sep. 30, 2014 Oncor [Member] Texas Competitive Electric Holdings Company LLC [Member]	Sep. 30, 2013 Oncor [Member] Texas Competitive Electric Holdings Company LLC [Member]	Sep. 30, 2014 Oncor [Member] Texas Competitive Electric Holdings Company LLC [Member]	Sep. 30, 2013 Oncor [Member] Texas Competitive Electric Holdings Company LLC [Member]	Dec. 31, 2013 Oncor [Member] Payable Attributable To Income Taxes [Member] Energy Future Holdings Corp. [Member]	Feb. 28, 2014 EFH Corp. [Member] Texas Competitive Electric Holdings Company LLC [Member] Pension Plan, Defined Benefit [Member]	Sep. 30, 2014 Texas Competitive Electric Holdings Company LLC [Member] Oncor [Member]	Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member] Oncor [Member]	Sep. 30, 2014 Texas Competitive Electric Holdings Company LLC [Member] Oncor [Member]	Sep. 30, 2013 Texas Competitive Electric Holdings Company LLC [Member] Oncor [Member]	Dec. 31, 2013 Texas Competitive Electric Holdings Company LLC [Member] Oncor [Member]	Sep. 30, 2014 Texas Competitive Electric Holdings Company LLC [Member] Oncor [Member] Minimum [Member] Rating-Agencies-Downgrades	Sep. 30, 2014 Texas Competitive Electric Holdings Company LLC [Member] Collateral posted [Member] Oncor [Member]	Dec. 31, 2013 Texas Competitive Electric Holdings Company LLC [Member] Collateral posted [Member] Oncor [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses From Transactions With Related Party, Allocated To Subsidiary														$ 0	$ 0	$ 3	$ 0	$ 0	$ 0	$ 4	$ 0
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party										2	0	3	0																		8	8	23	24
Income Taxes Receivable, Current	211	110
Related Party Transaction, Expenses from Transactions with Related Party																						0	3
Long-term debt, gross																								698
Related Party Transaction, Amounts of Transaction																																									281	273	746	728
Percentage Of Equity Method Investment Consolidated Revenues Related To Services Provided To Entity																										26.00%	28.00%
Due to Affiliate																																									152		152		135
Public Utilities, Delivery Fee Surcharge Remitted To Related Party																																			5	5	13	12
Due from Affiliate, Current									18
Due to Affiliate, Current					38	23	18	56																						7									5
Related Party Tax Expense, Due to Affiliates, Current																									10			17	24				163	60
Related Party Tax Expense, Due from Affiliates, Current				33
Related Party, Letter of Credit Posted as Collateral																																															9	9
Related Party, Event of Credit Rating Downgrade, Letter of Credit Required to be Posted to Secure Payment Obligations																																			170		170
Related Party, Event of Credit Rating Downgrade, Minimum Number of Rating Agencies Downgrade Below Investment Grade																																														2
Related Party Transaction, Reimbursement Due to Parent			1
Defined Benefit Plan, Contributions by Employer																																								$ 20