Oncor Electric Delivery 10-Q 6 Aug 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Aug. 06, 2018
Entity Registrant Name	ONCOR ELECTRIC DELIVERY CO LLC
Entity Central Index Key	1,193,311
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Amendment Flag	false
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		0
Oncor Electric Delivery Holdings Company LLC [Member]
Entity Outstanding Membership Interests		80.25%
Texas Transmission Investment LLC [Member]
Entity Outstanding Membership Interests		19.75%

Condensed Statements Of Consoli

Condensed Statements Of Consolidated Income - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	[1]	Jun. 30, 2018	Jun. 30, 2017
Condensed Statements Of Consolidated Income [Abstract]
Operating revenues (Note 4)	$ 1,021	$ 964		$ 2,011	$ 1,899
Operating expenses:
Wholesale transmission service	238	229		483	460
Operation and maintenance (Note 11)	203	166		422	354
Depreciation and amortization	168	193		334	387
Provision in lieu of income taxes (Note 11)	47	67		80	112
Taxes other than amounts related to income taxes	121	107		246	220
Total operating expenses	777	762		1,565	1,533
Operating income	244	202		446	366
Other income and (deductions) - net (Note 12)	(18)	(11)		(50)	(22)
Nonoperating benefit in lieu of income taxes	(4)	(6)		(11)	(11)
Interest expense and related charges (Note 12)	87	85		175	170
Net income	$ 143	$ 112		$ 232	$ 185
[1]	As adjusted for the retrospective adoption of ASU 2017-07, as discussed in Note 1.

Condensed Statements Of Consol3

Condensed Statements Of Consolidated Comprehensive Income - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017		Jun. 30, 2018	Jun. 30, 2017
Condensed Statements Of Consolidated Comprehensive Income [Abstract]
Net income	$ 143	$ 112	[1]	$ 232	$ 185
Other comprehensive income (loss):
Cash flow hedges – derivative value net loss recognized in net income (net of tax)					1
Defined benefit pension plans (net of tax)	1	1		2	1
Total other comprehensive income	1	1		2	2
Comprehensive income	$ 144	$ 113		$ 234	$ 187
[1]	As adjusted for the retrospective adoption of ASU 2017-07, as discussed in Note 1.

Condensed Statements Of Consol4

Condensed Statements Of Consolidated Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows - operating activities:
Net income	$ 232	$ 185
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	393	412
Provision in lieu of deferred income taxes	26	158
Other - net	(1)	(1)
Changes in operating assets and liabilities:
Regulatory accounts related to reconcilable tariffs (Note 5)	45	(27)
Other operating assets and liabilities	(145)	(89)
Cash provided by operating activities	550	638
Cash flows - financing activities:
Repayments of long-term debt (Note 7)	(144)
Change in short-term borrowings (Note 6)	346	367
Capital contributions from members (Note 9)	144
Distributions to members (Note 9)		(172)
Cash provided by financing activities	346	195
Cash flows - investing activities:
Capital expenditures (Note 11)	(926)	(856)
Other - net	10	8
Cash used in investing activities	(916)	(848)
Net change in cash and cash equivalents	(20)	(15)
Cash and cash equivalents - beginning balance	21	16
Cash and cash equivalents - ending balance	$ 1	$ 1

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 1	$ 21
Trade accounts receivable - net (Note 12)	686	635
Amounts receivable from members related to income taxes (Note 11)	4	26
Materials and supplies inventories - at average cost	107	91
Prepayments and other current assets	94	88
Total current assets	892	861
Investments and other property (Note 12)	118	113
Property, plant and equipment - net (Note 12)	15,500	14,879
Goodwill (Note 12)	4,064	4,064
Regulatory assets (Note 5)	2,093	2,180
Other noncurrent assets	11	23
Total assets	22,678	22,120
Current liabilities:
Short-term borrowings (Note 6)	1,296	950
Long-term debt due currently (Note 7)	931	550
Trade accounts payable (Note 11)	252	242
Amounts payable to members related to income taxes (Note 11)	13	21
Accrued taxes other than amounts related to income	116	190
Accrued interest	82	83
Other current liabilities	179	188
Total current liabilities	2,869	2,224
Long-term debt, less amounts due currently (Note 7)	5,044	5,567
Liability in lieu of deferred income taxes (Note 11)	1,545	1,517
Regulatory liabilities (Note 5)	2,878	2,807
Employee benefit obligations and other (Notes 10 and 12)	2,061	2,102
Total liabilities	14,397	14,217
Commitments and contingencies (Note 8)
Membership interests (Note 9):
Capital account — number of interests outstanding 2018 and 2017 - 635,000,000	8,380	8,004
Accumulated other comprehensive loss	(99)	(101)
Total membership interests	8,281	7,903
Total liabilities and membership interests	$ 22,678	$ 22,120

Condensed Consolidated Balance6

Condensed Consolidated Balance Sheets (Parenthetical) - shares	Jun. 30, 2018	Dec. 31, 2017
Condensed Consolidated Balance Sheets [Abstract]
Capital account, interests outstanding	635,000,000	635,000,000

Business and Significant Accoun

Business and Significant Accounting Policies	6 Months Ended
	Jun. 30, 2018
Business and Significant Accounting Policies [Abstract]
Business and Significant Accounting Policies	1. BUSINESS AND SIGNIFICANT ACCOUNTING POLICIES  Description of Business  References in this report to “we,” “our,” “us” and “the company” are to Oncor. See “Glossary” for definition of terms and abbreviations.  We are a regulated electricity transmission and distribution company principally engaged in providing delivery services to REPs that sell power in the north-central, eastern and western parts of Texas. We are a direct, majority-owned subsidiary of Oncor Holdings, which is a direct, wholly-owned subsidiary of STIH, a direct wholly-owned subsidiary of STH. In connection with the Sempra Acquisition, on March 9, 2018, STH became an indirect wholly- owned subsidiary of Sempra. Oncor Holdings owns 80.25% of our membership interests and Texas Transmission owns 19.75% of our membership interests. We are managed as an integrated business; consequently, there are no separate reportable business segments.  Various “ring-fencing” measures that had been taken to enhance our credit quality and the separateness between the Oncor Ring-Fenced Entities and its majority owner (formerly the Texas Holdings Group and now Sempra) continue to remain in effect after the Sempra Acquisition. These measures serve to mitigate our and Oncor Holdings’ credit exposure to Sempra and to reduce the risk that our assets and liabilities or those of Oncor Holdings would be substantively consolidated with the assets and liabilities of Sempra in connection with a bankruptcy of one or more Sempra entities. Such measures include, among other things: the 19.75% equity interest held by Texas Transmission; maintenance of separate books and records for the Oncor Ring-Fenced Entities; our board of directors being comprised of a majority of independent directors; and prohibitions on the Oncor Ring-Fenced Entities providing credit support to or receiving credit support from Sempra entities . The assets and liabilities of the Oncor Ring-Fenced Entities are separate and distinct from those of Sempra. None of the assets of the Oncor Ring-Fenced Entities are available to satisfy the debt or contractual obligations of Sempra entities . We do not bear any liability for debt or contractual obligations of Sempra, and vice versa. Accordingly, our operations are conducted, and our cash flows are managed, independently from Sempra. For more information on ring-fencing measures, see Note 2.  EFH Bankruptcy Proceedings and Change in Indirect Ownership of Oncor  In April 2014, EFH Corp. and the substantial majority of its direct and indirect subsidiaries at the time, including EFIH, EFCH and TCEH, commenced proceedings under Chapter 11 of the U.S. Bankruptcy Code. The Oncor Ring-Fenced Entities were not parties to the EFH Bankruptcy Proceedings. In connection with the plans of reorganization in the EFH Bankruptcy Proceedings, on March 9, 2018, Sempra acquired the 80.03% of Oncor’s membership interests owned indirectly by EFH Corp. and EFIH (Sempra Acquisition). See Note 2 for further information.  Basis of Presentation  These unaudited condensed financial statements should be read in conjunction with the audited financial statements and related notes included in the 2017 Form 10-K. In the opinion of Oncor management, all adjustments (consisting of normal recurring accruals) necessary for a fair presentation of the results of operations and financial position have been made. All intercompany items and transactions have been eliminated in consolidation. The results of operations for an interim period may not give a true indication of results for a full year due to seasonality. All dollar amounts in the financial statements and tables in the notes are stated in millions of U.S. dollars unless otherwise indicated.  Use of Estimates  Preparation of our financial statements requires management to make estimates and assumptions about future events that affect the reporting of assets and liabilities at the balance sheet dates and the reported amounts of revenue and expense, including fair value measurements. In the event estimates and/or assumptions prove to be different from actual amounts, adjustments are made in subsequent periods to reflect more current information. No material adjustments were made to previous estimates or assumptions during the current period.  Changes in Accounting Standards  Since May 2014, the Financial Accounting Standards Board (FASB) has issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers , along with other supplemental guidance (together, Topic 606). Topic 606 introduced new, increased requirements for disclosure of revenue in financial statements and guidance intended to eliminate inconsistencies in the recognition of revenue. We adopted Topic 606 effective January 1, 2018 using the modified retrospective approach and elected the practical expedient available that allows an entity to recognize revenue in the amount to which the entity has the right to invoice related to performance completed to date. Our r evenues are generally recognized when the underlying service has been provided in an amount prescribed by the related tariff. The new guidance did not change this pattern of recognition and therefore the adoption did not have a material effect on our reported results of operations, financial position or cash flows. Topic 606 also requires the separate presentation of “alternative revenue program” revenues on the income statement. We anticipate less than $20 million annually in alternative revenue program revenues related to our energy efficiency program and will disclose such activity in the notes to financial statements. See Note 4 for additional disclosures about revenues from contracts with customers.  In February 2016, the FASB issued ASU 2016-02 which created FASB Topic 842, Leases (Topic 842). Topic 842 amends previous GAAP to require the balance sheet recognition of substantially all lease assets and liabilities, including operating leases. Operating lease liabilities are not classified as debt for GAAP purposes under Topic 842 and are not treated as debt for regulatory purposes. Under current standards , all of Oncor’s existing leases meet the definition of an operating lease. Under the new rules, the recognition of any finance leases (currently known as capital leases) on the balance sheet would be classified as debt for GAAP purposes and are expected to be defined as debt for our regulatory capital structure purposes (see Note 9 for details) similar to the current capital lease treatment. We will be required to adopt Topic 842 by January 1, 2019 and we expect to use certain practical expedients and policy elections available under the guidance including a practical expedient to not assess whether existing land easements that were not previously accounted for as leases are or contain a lease under Topic 842, a n adoption method to not restate comparative periods and a policy election to forego the application of Topic 842 recognition requirements to short-term leases. The initial adoption of Topic 842 will affect our balance sheet, as our contracts for office space and fleet vehicles are currently clas sified as operating leases. Subsequent to adoption, to the extent Oncor enters into finance leases, its credit facility cov enants and capitalization ratios could be impacted. We continue to evaluate our contracts for proper treatment under the new standards and the estimated impact on our financial statements.  In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost , an amendment to Topic 715, Compensation – Retirement Benefits . ASU 2017-07 requires the non-service cost components of net retirement benefit plan costs be presented as non-operating in the income statement. In addition, only the service cost component of net retirement benefit plan cost is eligible for capitalization as part of inventory or property, plant and equipment. We adopted ASU 2017-07 on January 1, 2018. The presentation of costs is required to be applied on a retrospective basis while the capitalization eligibility requirement is applied on a prospective basis. The guidance allows a practical expedient that permits use of previously disclosed service costs and non-service costs of the Pension and OPEB Plans in the comparative periods as appropriate estimates when recasting the presentation of these costs in the income statements. We have elected this practical expedient. For cash flow purposes on a prospective basis, non-service costs will be reflected as a reduction to operating cash flows, offset by lower cash used in investing activities (lower capital expenditures). The new guidance did not have a material effect on our results of operations, financial position or net change in total cash flows and we do not expect the guidance to have a material effect on our rate-making process. For the three - and six- month periods ended June 30 , 2017, the adoption of ASU 2017-07 resulted in a reclassification of $8 million and $15 million from operation and maintenance expense to other income and (deductions), respectively, and a corresponding reclassification of $3 million and $6 million, respectively, from provision in lieu of income taxes to nonoperating pr ovision in lieu of income taxes. For the years 2015, 2016 and 2017, the reclassification amounts are $ 28 million, $28 million and $ 31 million from operation and maintenance expense to other income and (deductions), respectively, and a corresponding reclassification of $ 10 million, $10 million and $11 million, respectively, from provision in lieu of income taxes to nonoperating pr ovision in lieu of income taxes.  In February 2018, the FASB issued ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (ASU 2018-02). ASU 2018-02 allows a reclassification from accumulated other comprehensive income (AOCI) to capital accounts for stranded tax effects resulting from the TCJA. Under ASU 2018-02, an entity will be required to provide certain disclosures regarding stranded tax effects, including its accounting policy related to releasing the income tax effects from AOCI. We estimate our stranded tax effects in AOCI to be approximately $22 million. ASU 2018-02 can be applied either as of the beginning of the period of adoption or retrospectively as of the date of enactment of the TCJA and to each period in which the effect of the TCJA is recognized. ASU 2018-02 is effective for our 2019 annual reporting p eriod, including interim periods therein, with early adoption permitted. We have not yet selected the adoption method or the year in which we will adopt the standard. 

EFH Bankruptcy Proceedings and

EFH Bankruptcy Proceedings and Change in Indirect Ownership of Oncor	6 Months Ended
	Jun. 30, 2018
EFH Bankruptcy Proceedings and Change in Indirect Ownership of Oncor [Abstract]
EFH BANKRUPTCY PROCEEDINGS AND CHANGE IN INDIRECT OWNERSHIP OF ONCOR	2. EFH BANKRUPTCY PROCEEDINGS AND CHANGE IN INDIRECT OWNERSHIP OF ONCOR  In April 2014, E FH Corp. and the substantial majority of its direct and indirect subsidiaries at the time, including EFIH, EFCH and TCEH, commenced proceedings under Chapter 11 of the U.S. Bankruptcy Code. The Oncor Ring-Fenced Entities were not parties to the EFH Bankruptcy Proceedings. In 2016, pursuant to a plan of reorganization confirmed by the bankruptcy court, the TCEH Debtors exited bankruptcy pursuant to the Vistra Spin-Off. As a result of the Vistra Spin-Off, Vistra and its subsidiaries, including Luminant and TXU Energy, ceased to be related parties of ours as of October 3, 2016. See Note 11 for details of Oncor’s related-party transactions with members of the Texas Holdings Group. In connection with the plans of reorganization in the EFH Bankruptcy Proceedings, on March 9, 2018, Sempra acquired the 80.03% of Oncor’s membership interests owned indirectly by EFH Corp. and EFIH (Sempra Acquisition), as discussed in further detail below.  Prior to consummation of the Sempra Acquisition, EFH Corp. entered into various merger agreements , which failed to close, with other parties in connection with the EFH Bankruptcy Proceedings and the potential transfer of its indirect ownership interest in Oncor. For a summary of those merger agreements and related regulatory proceedings, please see Note 2 to Financial Statements in the 2017 Form 10-K.  Sempra Acquisition  In August 2017, EFH Corp. and EFIH entered into an Agreement and Plan of Merger (Sempra Merger Agreement) with Sempra and one of its wholly-owned subsidiaries (collectively, the Sempra Parties) th at contemplated the Sempra Parties acquiring the ownership interests in Oncor that were indirectly held by EFH Corp. The Sempra Acquisition closed on March 9, 2018. As a result of the Sempra Acquisition, EFH Corp. merged with an indirect subsidiary of Sempra, with EFH Corp. (renamed STH) continuing as the surviving company and an indirect, wholly-owned subsidiary of Sempra. The Sempra Merger Agreement did not impose any conditions on the EFH Debtors regarding Texas Transmission’s minority interest in Oncor. Accordingly, the Sempra Merger Agreement provided for the acquisition by Sempra of the 80.03% of Oncor’s membership interests owned indirectly by EFH Corp. and EFIH. In accordance with the Sempra Merger Agreement, Sempra paid cash consideration of approximately $9.45 billion to acquire the indirect 80.03% outstanding membership interest in Oncor. In addition, in a separate transaction , Oncor Holdings acquired 0.22% of the outstanding membership interests in Oncor from Investment LLC. After the Sempra Acquisition, Texas Transmission continued to own 19.75% of Oncor’s outstanding membership interests. The Sempra Merger Agreement was consummated on March 9, 2018 after obtaining the approval of the bankruptcy court in the EFH Bankruptcy Proceedings, the Federal Communications Commission and the PUCT.  Pursuant to the terms of the Sempra Merger Agreement, in October 2017, Oncor and Sempra filed in PUCT Docket No 47675 a jo int application with the PUCT seeking certain regulatory approvals with respect to the transactions contemplated by the amended joint plan of reorganization filed in September 2017 by the EFH Debtors (Sempra Plan). At its open meeting on March 8, 2018, the PUCT approved a final order adopting a settlement stipulation allowing the Sempra Acquisition to proceed . For more information regarding the Sempra Settlement Stipulation and the proceedings in PUCT Docket No. 47675, see “Sempra PUCT Proceedings” below.  In connection with the closing of the Sempra Acquisition, Oncor’s Limited Liability Company Agreement was amended and restated in its entirety on March 9, 2018. The Limited Liability Company Agreement, among other things, provides for the management of Oncor by a board of directors consisting of 13 members, including seven “disinterested directors” (as defined in the Limited Liability Company Agreement), two directors designated indirectly by Sempra, two directors designated by Texas Transmission (subject to certain conditions) and two directors that are current or former officers of Oncor.  Management Equity Purchase  On March 9, 2018, Oncor entered into an Interest Transfer Agreement (OMI Agreement) with Investment LLC, Oncor Holdings and Sempra. Pursuant to the 2008 Equity Interests Plan for Key Employees of Oncor Electric Delivery Company LLC and its a ffiliates, certain members of Oncor’s management, including Oncor’s executive officers and independent directors on Oncor’s board of directors, were granted the opportunity to purchase Class B equity interests (Class B Interests) in Investment LLC, an entity whose only assets consist of equity interests in Oncor. Investment LLC held 1,396,008 of the outstanding limited liability company interests in Oncor (the OMI Interests), which represented 0.22% of the outstanding membership interests in Oncor. For a description of the amounts of Class B Interests that were beneficially owned by members of Oncor’s board of directors and each of Oncor’s named executive officers, see “Security Ownership of Certain Beneficial Owners and Management and Related Equity Holder Matters – Security Ownership of Equity Interests of Oncor of Certain Beneficial Owners and Management.” in the 2017 Form 10-K.  Pursuant to the OMI Agreement, in connection with the closing of the Sempra Acquisition, Investment LLC transferred to Oncor Holdings all of the OMI Interests in exchange for $26 million in cash, which represents approximately $18.60 for each OMI Interest.  PUCT Matters Related to EFH Bankruptcy Proceedings  Previous Merger Agreement PUCT Proceedings  Prior to consummation of the Sempra Acquisition, EFH Corp. entered into various merger agreements , which failed to close, with other parties in connection with the EFH Bankruptcy Proceedings and the potential transfer of its indirect ownership interest in Oncor. For a summary of those merger agreements and related PUCT proceedings, please see Note 2 to Financial Statements in the 2017 Form 10-K.  Sempra PUCT Proceedings  Pursuant to the terms of the Sempra Merger Agreement, in October 2017 Oncor and Sempra filed in PUCT Docket No. 47675 a joint application with the PUCT seeking certain regulatory approvals with respect to the Sempra Plan. In December 2017, Oncor and Sempra entered into a stipulation with the Staff of the PUCT, the Office of Public Utility Counsel, the Steering Committee of Cities Served by Oncor and the Texas Industrial Energy Consumers reflecting the parties’ settlement of all issues in the PUCT proceeding regarding the joint application. On January 5, 2018, Oncor, Sempra and the Staff of the PUCT made a joint filing with the PUCT requesting that the PUCT approve the acquisition, consistent with the governance, regulatory and operating commitments in a revised stipulation joined by two additional parties. On January 23, 2018, Oncor and Sempra filed an additional revision to the revised stipulation (Sempra Settlement Stipulation) and announced that two more parties had joined in the Sempra Settlement Stipulation. On February 2, 2018, Oncor and Sempra announced that all of the intervenors in PUCT Docket No. 47675 had signed on to the Sempra Settlement Stipulation. At its February 15, 2018 open meeting, the PUCT directed PUCT Staff to prepare an order based on the Sempra Settlement Stipulation for consideration by the PUCT at its open meeting on March 8, 2018. At the open meeting, the PUCT approved the final order.  T he parties to the Sempra Settlement Stipulation agreed that Sempra’s acquisition of EFH Corp. was in the public interest and would bring substantial benefits. The Sempra Settlement Stipulation requested that the PUCT approve the Sempra Acquisition. The joint application filed with the PUCT and the Sempra Settlement Stipulation outline certain ring-fencing measures, governance mechanisms and restrictions that apply after the Sempra Acquisition. As a result of these ring-fencing measures, Sempra will not control Oncor, and the ring-fencing measures limit Sempra’s ability to direct the management, policies and operations of Oncor, including the deployment or disposition of Oncor’s assets, declarations of dividends, strategic planning and other important corporate issues and actions. These limitations include limited representation on the board of directors of Oncor.  Pursuant to the order issued by PUCT in PUCT Docket No. 47675 with respect to its approval of the transaction contemplated by the Sempra Plan (Sempra Order), following the consummation of the Sempra Acquisition, the board of directors of Oncor is required to consist of thirteen members and be constituted as follows: · seven members, which we refer to as disinterested directors, (i) shall be independent directors in all material respects under the rules of the New York Stock Exchange in relation to Sempra and its subsidiaries and affiliated entities and any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, and (ii) shall have no material relationship with Sempra or its affiliates or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings at the time of the Sempra Acquisition or within the previous ten years; · two members shall be designated by Sempra (through Oncor Holdings) ; · two members shall be appointed by Texas Transmission; and · two members shall be current or former officers of Oncor (the Oncor Officer Directors), initially Robert S. Shapard and E. Allen Nye, Jr., who are the chair of the Oncor board and chief executive of Oncor, respectively.  In order for a current or former officer of Oncor to be eligible to serve as an Oncor Officer Director, such officer cannot have worked for Sempra or any of its affiliates (excluding Oncor Holdings and Oncor) or any other entity with a direct or indirect ownership interest in Oncor or Oncor Holdings in the ten year period prior to such officer being employed by Oncor. Oncor Holdings, at the direction of STIH (a subsidiary of STH), which is a wholly - owned indirect subsidiary of, and controlled by, Sempra following the Sempra Acquisition), has the right to nominate and/or seek the removal of the Oncor Officer Directors, with such nomination or removal subject to approval by a majority of the Oncor board of directors.  In addition, the Sempra Order provides that Oncor’s board cannot be overruled by the board of Sempra or any of its subsidiaries on dividend policy, the issuance of dividends or other distributions (except for contractual tax payments), debt issuance, capital expenditures, operation and maintenance expenditures, management and service fees, and appointment or removal of board members, provided that certain actions may also require the additional approval of the Oncor Holdings board of directors. The Sempra Order also provides that any changes to the size, composition, structure or rights of the board must first be approved by the PUCT. In addition, if Sempra acquires Texas Transmission’s interest in Oncor, the two board positions on Oncor’s board of directors that Texas Transmission is entitled to appoint shall be eliminated and the size of Oncor’s board of directors will be reduced by two.  Additional regulatory commitments, governance mechanisms and restrictions provided in the Sempra Order include, among others:  · A majority of the disinterested directors of Oncor must approve any annual or multi-year budget if the aggregate amount of capital expenditures or operating and maintenance expenditures in such budget is more than a 10% increase or decrease from the corresponding amounts of such expenditures in the budget for the preceding fiscal year or multi-year period, as applicable;  · Oncor will make minimum aggregate capital expenditures equal to at least $7.5 billion over the period from January 1, 2018 through December 31, 2022 (subject to certain possible adjustments);  · Sempra was required to make, within 60 days after the Sempra Acquisition, its proportionate share of the aggregate equity investment in Oncor in an amount necessary for Oncor to achieve a capital structure consisting of 57.5% long-term debt to 42.5% equity, as calculated for regulatory purposes;  Sempra contributed $117 million in cash commensurate with its ownership interest to Oncor on April 23, 2018 , as discussed in further detail in Note 9 .  · Oncor may not pay any dividends or make any other distributions (except for contractual tax payments) if a majority of its disinterested directors determines that it is in the best interests of Oncor to retain such amounts to meet expected future requirements;  · At all times, Oncor will remain in compliance with the debt-to-equity ratio established by the PUCT from time to time for ratemaking purposes, and Oncor will not pay dividends or other distributions (except for contractual tax payments), if that payment would cause its debt-to-equity ratio to exceed the debt-to-equity ratio approved by the PUCT;  · If the credit rating on Oncor’s senior secured debt by any of the three major rating agencies falls below BBB (or the equivalent), Oncor will suspend dividends and other distributions (except for contractual tax payments), unless otherwise allowed by the PUCT;  · Without the prior approval of the PUCT, neither Sempra nor any of its affiliates (excluding Oncor) will incur, guaranty or pledge assets in respect of any indebtedness that is dependent on the revenues of Oncor in more than a proportionate degree than the other revenues of Sempra or on the stock of Oncor, and there will be no debt at STH or STIH at any time following the closing of the Sempra Acquisition;  · Neither Oncor nor Oncor Holdings will lend money to or borrow money from Sempra or any of its affiliates (other than Oncor subsidiaries), or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, and neither Oncor nor Oncor Holdings will share credit facilities with Sempra or any of its affiliates (other than Oncor subsidiaries), or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings;  · Oncor will not seek recovery in rates of any expenses or liabilities related to EFH Corp.’s bankruptcy, or (1) any tax liabilities resulting from the Vistra Spin-Off, (2) any asbestos claims relating to non-Oncor operations of EFH Corp. or (3) any make-whole claims by holders of debt securities issued by EFH Corp. or EFIH, and Sempra was required to file with the PUCT a plan providing for the extinguishment of the liabilities described in items (1) through (3) above, which protects Oncor from any harm (which plan was filed with the PUCT on April 6, 2018 in PUCT Docket No. 48119);  · There must be maintained certain “separateness measures” that reinforce the financial separation of Oncor from STH and STH’s owners, including a requirement that dealings between Oncor, Oncor Holdings and their subsidiaries with Sempra, any of Sempra’s other affiliates or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, must be on an arm’s-length basis, limitations on affiliate transactions, separate recordkeeping requirements and a prohibition on pledging Oncor assets or stock for any entity other than Oncor;  · No transaction costs or transition costs related to the Sempra Acquisition (excluding Oncor employee time) will be borne by Oncor’s customers nor included in Oncor’s rates;  · Sempra will continue to hold indirectly at least 51% of the ownership interests in Oncor and Oncor Holdings for at least five years following the closing of the Sempra Acquisition, unless otherwise specifically authorized by the PUCT; and  · Oncor will provide bill credits to electric delivery rates for ultimate credits to customers in an amount equal to 90% of any interest rate savings achieved due to any improvement in its credit ratings or market spreads compared to those as of June 30, 2017 until final rates are set in the next Oncor base rate case filed after PUCT Docket No. 46957 (except that savings will not be included in credits if already realized in rates); and one year after the Sempra Acquisition, Oncor will provide bill credits to electric delivery rates for inclusion in customer bills equal to 90% of any synergy savings until final rates are set in the next Oncor base rate proceeding after the 2017 rate review (PUCT Docket No. 46957), at which time any total synergy savings shall be reflected in Oncor’s rates. 

Regulatory Matters

Regulatory Matters	6 Months Ended
	Jun. 30, 2018
Regulatory Matters [Abstract]
REGULATORY MATTERS	3. REGULATORY MATTERS  DCRF (PUCT Docket No. 48231 )  On April 5, 2018, Oncor filed with the PUCT, as well as cities with original jurisdiction over Oncor’s rates, an application for approval of a distribution cost recovery factor (DCRF). The DCRF will allow Oncor to recover, primarily through its tariff for retail delivery service, certain costs related to its 2017 distribution investments. The DCRF application we filed requested a $19 million increase in annual distribution revenues. On June 13, 2018, Oncor filed an unopposed stipulation that reduced the annual distribution revenue increase from $19 million to $15 million. Subject to review and approval by the PUCT, the interim distribution tariffs beco me effective September 1, 2018.  Application to Decrease Rates Based on the TCJA of 2017 ( PUCT Doc k e t No. 48325 )  On May 1, 2018, Oncor made a filing related to the impacts of the TCJA, including the reduced corporate income tax rate from 35% to 21% , for retail customers and amortization of excess deferred federal income taxes. Oncor will revise its tariffs to effect these changes and reduce rates to end-use customers going forward. In addition, for retail customers, Oncor will propose a refund of the tax amounts collected and deferred since January 1, 2018, through the date the changed tariffs are effective. For wholesale customers, Oncor will propose a refund of the tax amounts collected and deferred since January 1, 2018 through March 26, 2018, as Oncor’s new wholesale rate in PUCT Docket No. 47988 reflects the new TCJA rate and went into effect March 27, 2018. On July 1, 2018, Oncor's proposed new TCOS rate was approved to go into effect on an interim basis. The new TCOS rate results in a reduction of about $15 million of annualized transmission base revenue requirement. The reduction is due to amortization of excess deferred federal income taxes due to the TCJA in 2017 .  The pass-through of the impacts of the TCJA to ratepayers is not expected to impact net income . Amortization of excess deferred taxes will result in lower cash inflows as a result of reduced rates to end-use customers . In the filing, we proposed a total net decrease in the revenue requirement used to set transmission and distribution rates of approximately $181 million annually as compared to the revenue requirement approved in Oncor’s most recent rate review, PUCT Docket No. 46957. The proposal includes annual rate reduction s of $144 million related to the reduction in income tax expense currently included in rates and $37 million related to the amortization of excess deferred income taxes over the lives of related assets. The final amortization periods and resulting amount of the rate reduction will be determined in the Docket. 

Revenues

Revenues	6 Months Ended
	Jun. 30, 2018
Revenues [Abstract]
REVENUES	4. REVENUES  General  Our revenue is billed monthly under tariffs approved by the PUCT and the majority of revenues are related to providing electric delivery service to consumers. Tariff rates are designed to recover the cost of providing electric delivery service to customers including a reasonable rate of return on invested capital. As the units delivered can be directly measured, our revenues are recognized when the underlying service has been provided in an amount prescribed by the related tariff. We recognize revenue in the amount that we have the right to invoice. Substantially all of our revenues are from contracts with customers (Topic 606 revenues) except for alternative revenue program revenues discussed below.  Reconcilable Tariffs  The PUCT has designated certain tariffs (primarily TCRF, EECRF and previously AMS surcharges) as reconcilable, which means the differences between amounts billed under these tariffs and the related incurred costs are deferred as either regulatory assets or regulatory liabilities. Accordingly, at prescribed intervals, future tariffs are adjusted to either repay regulatory liabilities or collect regulatory assets.  Alternative Revenue Program  The PUCT has implemented an incentive program allowing us to earn performance bonuses by exceeding PUCT energy efficiency program targets. This incentive program is considered an “alternative revenue program” and the related performance bonus revenues are outside of the scope of Topic 606. Annual performance bonuses are recognized as revenue when approved by the PUCT, typically in the third or fourth quarter each year.  As a result of the 2017 rate review order effective November 26, 2017, the AMS surcharges ceased and AMS related expenses and return became recoverable through distribution base rates.  Disaggregation of Revenues  The following table reflects electric delivery revenues disaggregated by tariff for the three and six months ended June 30, 2018 :   Three Months Ended June 30, Six Months Ended June 30,  Operating revenues 2018 2018  Revenues contributing to earnings:  Distribution base revenues $ 529 $ 1,036  Transmission base revenues (TCOS revenues)  Billed to third-party wholesale customers 141 266  Billed to REPs serving Oncor distribution customers, through TCRF 79 157  Total transmission base revenues 220 423  Other miscellaneous revenues 16 31  Total revenues contributing to earnings 765 1,490   Revenues collected for pass-through expenses:  TCRF - third-party wholesale transmission service 238 483  EECRF and other regulatory charges 18 38  Revenues collected for pass-through expenses 256 521   Total operating revenues $ 1,021 $ 2,011  Customers  Our distribution customers consist of approximately 90 REPs and certain electric cooperatives in our certificated service area. The consumers of the electricity we deliver are free to choose their electricity supplier from REPs who compete for their business. REP subsidiaries of our two largest counterparties represented 20% and 17% of our total operating revenues for the three months ended June 30, 2018, and 22% and 18% of our total operating revenues for the six months ended June 30, 2018 . No other customer represented more than 10% of our total operating revenues. Our transmission base revenues are collected from load serving entities benefitting from our transmission system. Our transmission customers consist of municipalities, electric cooperatives and other distribution companies.  Variability  Our revenues and cash flows are subject to seasonality, timing of customer billings, weather conditions and other electricity usage drivers, with revenues being highest in the summer. Payment is due 35 days after invoicing. Under a PUCT rule relating to the Certification of Retail Electric Providers, write-offs of uncollectible amounts owed by nonaffiliated REPs are recoverable as a regulatory asset.  Pass-through expenses  Expenses which are allowed to be passed-through to customers (primarily, third party wholesale transmission service and energy efficiency program costs) are generally recognized as revenue at the time the costs are incurred. Franchise taxes are assessed by local governmental bodies, based on kWh delivered and are not a “pass-through” item. The rates we charge customers are intended to recover the franchise taxes, but we are not acting as an agent to collect the taxes from customers; therefore, franchise taxes are reported as a principal component of “taxes other than amounts related to income taxes” instead of a reduction to “revenues” in the income statement.

Regulatory Assets and Liabiliti

Regulatory Assets and Liabilities	6 Months Ended
	Jun. 30, 2018
Regulatory Assets and Liabilities [Abstract]
REGULATORY ASSETS AND LIABILITIES	 5 . REGULATORY ASSETS AND LIABILITIES  Recognition of regulatory assets and liabilities and the periods over which they are to be recovered or refunded through rate regulation are determined by the PUCT. Components of our regulatory assets and liabilities as of June 30, 2018 and December 31, 2017 are provided in the table below. Amounts not earning a return through rate regulation are noted.   Remaining Rate Recovery/Amortization Period at Carrying Amount At  June 30, 2018 June 30, 2018 December 31, 2017   Regulatory assets:  Employee retirement costs being amortized 10 years $ 314 $ 331  Unrecovered employee retirement costs incurred since the last rate review period (a) To be determined 30 30  Employee retirement liability (a)(b)(c) To be determined 818 854  Employee retirement plans - non-service costs Lives of related assets 22 -  Self-insurance reserve (primarily storm recovery costs) being amortized 10 years 373 394  Unrecovered self-insurance reserve incurred since the last rate review period (a) To be determined 50 49  Securities reacquisition costs Lives of related debt 11 12  Deferred conventional meter and metering facilities depreciation 3 years 47 57  Under-recovered AMS costs 10 years 195 206  Excess deferred income taxes To be determined 202 197  Energy efficiency performance bonus (b) 1 year or less 6 12  Other regulatory assets Various 25 38  Total regulatory assets 2,093 2,180   Regulatory liabilities:  Estimated net removal costs Lives of related assets 992 954  Excess deferred income taxes To be determined 1,794 1,789  Federal income taxes - over-collected due to TCJA rate change To be determined 49 -  Over-recovered wholesale transmission service expense (b) 1 year or less 16 47  Other regulatory liabilities Various 27 17  Total regulatory liabilities 2,878 2,807  Net regulatory assets (liabilities) $ (785) $ (627) ____________ (a) Recovery is specifically authorized by statute or by the PUCT, subject to reasonableness review. (b) Not earning a return in the regulatory rate-setting process. (c) Represents unfunded liabilities recorded in accordance with pension and OPEB accounting standards.

Short-Term Borrowings

Short-Term Borrowings	6 Months Ended
	Jun. 30, 2018
Short-Term Borrowings [Abstract]
SHORT-TERM BORROWINGS	6. SHORT-TERM BORROWINGS  At June 30, 2018 and December 31, 2017, outstanding short-term borrowings under our commercial paper program (CP Program) and revolving credit facility (Credit Facility) consisted of the following:   At June 30, At December 31,  2018 2017  Total borrowing capacity $ 2,000 $ 2,000  Commercial paper outstanding (a) (1,296) -  Credit facility outstanding (b) - (950)  Letters of credit outstanding (c) (9) (9)  Available unused credit $ 695 $ 1,041 ____________ a) The weighted average interest rate for commercial paper at June 30, 2018 was 2.49% . . b) The weighted average interest rate for the credit facility at December 31, 2017 was 2.62% . c) Interest rates on outstanding letters of credit at June 30, 2018 and December 31, 207 were 1.200% and 1.325% , respectively, based on our credit ratings. Commercial Paper Program  In March 2018 , we established the CP Program, under which we may issue unsecured commercial paper notes (Notes) on a private placement basis up to a maximum aggregate amount outstanding at any time of $2.0 billion. We also entered into commercial paper dealer agreements (Dealer Agreements) with commercial paper dealers (Dealers). The Dealer Agreements are substantially identical in all material respects except as to the parties thereto. A national bank acts as the issuing and paying agent under the CP Program pursuant to the terms of an issuing and paying agent agreement.  T he proceeds of Notes issued under the CP Program are used for working capital and general corporate purposes. The CP Program obtains liquidity support from our Credit Facility discussed below . If at any time funds are not available on favorable terms under the CP Program, we may utilize the Credit Facility for funding.  The Dealer Agreements provide the terms under which the Dealers will either purchase from us or arrange for the sale by us of Notes pursuant to an exemption from federal and state securities laws. The Dealer Agreements contain customary representations, warranties, covenants and indemnification provisions. The maturities of the Notes will vary, but may not exceed 364 days from the date of issue. The face or principal amount of Notes outstanding under the CP Program at any time may not exceed $2.0 billion. Th e Notes will be sold at a discount from par or, alternatively, will be sold at par and bear interest at rates that will vary based on market conditions at the time of the issuance of the Notes. The rate of interest on any Note will depend on whether the Note will bear interest on a fixed rate or a floating rate basis.  From time to time, one or more of the Dealers and certain of their respective affiliates have provided, and may in the future provide, commercial banking, investment banking and other financial advisory services to us and our affiliates for which the Dealers have received or will receive customary fees and expenses. In addition, certain of the Dealers or their affiliates are lenders under the Credit Facility.  Revolving Credit Facility  At June 30, 2018 , we had a $2.0 billion unsecured revolving credit facility (Credit Facility) to be used for working capital and general corporate purposes, issuances of letters of credit and support for commercial paper issuances . We may request increases in our borrowing capacity in incremen ts of not less than $100 million, n ot to exceed $400 million in the aggregate provided certain conditions are met, including lender approvals. The Credit Facility has a five -year term expiring in November 2022 and gives us the option of requesting up to two one -year extensions, with such extensions subject to certain conditions and lender approvals. Borrowings are classified as short-term on the balance sheet. At June 30, 2018, we had no outstanding borrowings under the Credit Facility.  Borrowings under the Credit Facility bear interest at per annum rates equal to, at our option, (i) LIBOR plus a spread ranging from 0 .875% to 1.50% depending on credit ratings assigned to our senior secured non-credit enhanced long-term debt or (ii) an alternate base rate (the highest of (1) the prime rate of JPMorgan Chase, (2) the federal funds effective rate plus 0.50% , and (3) adjusted LIBOR plus 1.00% ) plus a spread ranging from 0.00% to 0.50% depending on credit ratings assigned to our senior secured non-credit enhanced long-term debt. At June 30, 2018 , the applicable interest rate for any outstanding borrowings would have been LIBOR plus 1.00% . Amounts borrowed under the Credit Facility , once repaid, can be borrowed again from time to time.  An unused commitment fee is payable quarterly in arrears and upon termination or commitment reduction at a rate equal to 0.075% to 0.225% (such spread depending on certain credit ratings assigned to our senior secured debt) of the daily unused commitments under the Credit Facility . At June 30, 2018 , a commitment fee (at a rate of 0.100% per annum) was payable on the unfunded commitments under the Credit Facility, based on our current credit ratings.  Letter of credit fees on the stated amount of letters of credit issued under the Credit Facility are payable to the lenders quarterly in arrears and upon termination at a rate per annum equal to the spread over adjusted LIBOR. Customary fronting and administrative fees are also payable to letter of credit fronting banks.  Under the terms of the Credit Facility, the commitments of the lenders to make loans to us are several and not joint. Accordingly, if any lender fails to make loans to us, our available liquidity could be reduced by an amount up to the aggregate amount of such lender’s commitments under the facility.  The Credit Facility contains customary covenants for facilities of this type, restricting, subject to certain exceptions, us and our subsidiaries from, among other things: incurring certain additional liens (not including liens relating to obligations secured pursuant to our Deed of Trust, which are permitted); entering into mergers and consolidations; sales of substantial assets and acquisitions and investments in subsidiaries. In addition, the Credit Facility requires that we maintain a consolidated senior debt-to-capitalization ratio of no greater than 0.65 to 1.00 and observe certain customary reporting requirements and other affirmative covenants. For purposes of the ratio, debt is calculated as indebtedness defined in the Credit Facility (principally, the sum of long-term debt, any capital leases, short-term debt and debt due currently in accordance with GAAP). Capitalization is calculated as membership interests determined in accordance with GAAP plus indebtedness described above. At June 30, 2018 , we were in compliance with this and all other covenants.

Long-Term Debt

Long-Term Debt	6 Months Ended
	Jun. 30, 2018
Long-Term Debt [Abstract]
LONG-TERM DEBT	7. LONG-TERM DEBT  Our senior notes are secured by a first priority lien on certain transmission and distribution assets equally and ratably with all of Oncor’s other secured indebtedness. See “Deed of Trust” below for additional information. At June 30, 2018 and December 31, 2017, our long-term debt consisted of the following:   June 30, December 31,  2018 2017   Secured:  6.800% Fixed Senior Notes due September 1, 2018 $ 550 $ 550  2.150% Fixed Senior Notes due June 1, 2019 250 250  5.750% Fixed Senior Notes due September 30, 2020 126 126  4.100% Fixed Senior Notes due June 1, 2022 400 400  7.000% Fixed Debentures due September 1, 2022 800 800  2.950% Fixed Senior Notes due April 1, 2025 350 350  7.000% Fixed Senior Notes due May 1, 2032 500 500  7.250% Fixed Senior Notes due January 15, 2033 350 350  7.500% Fixed Senior Notes due September 1, 2038 300 300  5.250% Fixed Senior Notes due September 30, 2040 475 475  4.550% Fixed Senior Notes due December 1, 2041 400 400  5.300% Fixed Senior Notes due June 1, 2042 500 500  3.750% Fixed Senior Notes due April 1, 2045 550 550  3.800% Fixed Senior Notes due September 30, 2047 325 325  Secured long-term debt 5,876 5,876  Unsecured:  Term loan credit agreement due no later than March 26, 2019 131 275  Total long-term debt 6,007 6,151  Unamortized discount and debt issuance costs (32) (34)  Less amount due currently (931) (550)  Long-term debt, less amounts due currently $ 5,044 $ 5,567  Debt-Related Activity in 2018  Debt Repayments  Repayments of long-term debt in the six months ending June 30, 2018 totaled $144 million representing principal repayment on the t erm loan credit agreement.  Deed of Trust  Our secured indebtedness is secured equally and ratably by a first priority lien on property we acquired or constructed for the transmission and distribution of electricity. The property is mortgaged under the Deed of Trust. The Deed of Trust permits us to secure indebtedness (excluding borrowings under the CP Program, the Credit Facility and the term loan credit agreement) with the lien of the Deed of Trust up to the aggregate of (i) the amount of available bond credits, and (ii) 85% of the lower of the fair value or cost of certain property additions that could be certified to the Deed of Trust collateral agent. At June 30, 2018 , the amount of available bond credits was $3.038 billion and the amount of future debt we could secure with property additions, subject to those property additions being certified to the Deed of Trust collateral agent, was $2.882 billion.  Fair Value of Long-Term Debt  At June 30, 2018 and December 31, 2017, the estimated fair value of our long-term debt (including current maturities) totaled $6.652 billion and $7.153 billion, respectively, and the carrying amount totale d $5.975 billi on and $6.117 billion, respectively. The fair value is estimated using observable market data, representing Level 2 valuations under accounting standards related to the determination of fair value.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies [Abstract]
COMMITMENTS AND CONTINGENCIES	8. COMMITMENTS AND CONTINGENCIES  EFH Bankruptcy Proceedings and Change in Indirect Ownership of Oncor  In April 2014 , the Debtors commenced the EFH Bankruptcy Proceedings. T he Oncor Ring-Fenced Entities were not parties to the EFH Bankruptcy Proceedings. See Note 2 for further information regarding the resolution of the EFH Bankruptcy Proceedings and the change in control of our indirect majority owner in connection with such proceedings and Note 11 for our related-party transactions involving members of the Texas Holdings Group.  Legal/Regulatory Proceedings  We are involved in various legal and administrative proceedings in the normal course of business, the ultimate resolution of which, in the opinion of management, should not have a material effect upon our financial position, results of operations or cash flows. See Note 3 in this report and Note 8 to Financial Statements in our 2017 Form 10-K for additional information regarding our legal and regulatory proceedings. 

Membership Interests

Membership Interests	6 Months Ended
	Jun. 30, 2018
Membership Interests [Abstract]
MEMBERSHIP INTERESTS	9. MEMBERSHIP INTERESTS  Cash Distributions   Distributions are limited by our required regulatory capital structure to be at or below the assumed debt-to-equity ratio established periodically by the PUCT for ratemaking purposes, which is 57.5% debt to 42.5% equity effective November 27, 2017. At June 30, 2018, $137 million was available for distribution to our members, as our regulatory capitalization ratio was 56.75% debt to 43.25% equity. The PUCT has the authority to determine what types of debt and equity are included in a utility’s debt-to-equity ratio. For purposes of this ratio, debt is calculated as long-term debt including capital leases plus unamortize d gains on reacquired debt less unamortized issuance expenses, premiums and losses on reacquired debt. Equity is calculated as membership interests determined in accordance with GAAP, excluding the effects of the acquisition accounting resulting from PUCT Docket No. 34077 (which included recording the initial goodwill and fair value adjustments and subsequent related impairments and amortization).  On July 25, 2018, our board of directors declared a cash distribution of $30 million, which was paid to our members on August 1, 2018.  Cash Contributions   In April 2018, our members made capital contributions of $144 million , which was used to pay down a portion of our term loan credit agreement .    Membership Interests  The following table presents the changes to membership interests during the six months ended June 30, 2018 and 2017:   Capital Accounts Accumulated Other Comprehensive Income (Loss) Total Membership Interests   Balance at December 31, 2017 $ 8,004 $ (101) $ 7,903  Net income 232 - 232  Capital contributions 144 - 144  Defined benefit pension plans (net of tax) - 2 2  Balance at June 30, 2018 $ 8,380 $ (99) $ 8,281   Balance at December 31, 2016 $ 7,822 $ (111) $ 7,711  Net income 185 - 185  Distributions (172) - (172)  Net effects of cash flow hedges (net of tax) - 1 1  Defined benefit pension plans (net of tax) - 1 1  Balance at June 30, 2017 $ 7,835 $ (109) $ 7,726  Accumulated Other Comprehensive Income (Loss)  The following table presents the changes to accumulated other comprehensive income (loss) for the six months ended June 30, 2018 and 2017:   Cash Flow Hedges – Interest Rate Swap Defined Benefit Pension and OPEB Plans Accumulated Other Comprehensive Income (Loss)   Balance at December 31, 2017 $ (18) $ (83) $ (101)  Defined benefit pension plans (net of tax) - 2 2  Amounts reclassified from accumulated other comprehensive income (loss) and reported in interest expense and related charges - - -  Balance at June 30, 2018 $ (18) $ (81) $ (99)   Balance at December 31, 2016 $ (20) $ (91) $ (111)  Defined benefit pension plans (net of tax) - 1 1  Amounts reclassified from accumulated other comprehensive income (loss) and reported in interest expense and related charges 1 - 1  Balance at June 30, 2017 $ (19) $ (90) $ (109) 

Pension and OPEB Plans

Pension and OPEB Plans	6 Months Ended
	Jun. 30, 2018
Pension And OPEB Plans [Abstract]
PENSION AND OPEB PLANS	 10. PENSION AND OPEB PLANS  Pension Plans  We sponsor the Oncor Retirement Plan and also have liabilities under the Vistra Retirement Plan, both of which are qualified pension plans under Section 401(a) of the Internal Revenue Code of 1986, as amended, and are subject to the provisions of ERISA. Employees do not contribute to either plan. We also have a supplemental pension plan for certain employees whose retirement benefits cannot be fully earned under the qualified retirement plans. See Note 10 to Financial Statements in our 2017 Form 10-K for additional information regarding pension plans.  OPEB Plans  We currently sponsor the Oncor OPEB Plan s . One plan covers our eligible current and future retirees, excluding certain eligible retirees of EFH Corp./Vistra whose employment service was assigned to both Oncor (or a predecessor regulated utility business) and a non-regulated business of EFH Corp . /Vistra which are now part of a separate plan discussed below.  Effective January 1, 2018, we established a second plan to cover retirees whose employment included service that has been assigned to both Oncor (or a predecessor regulated utility business) and non-regulated businesses of EFH Corp./Vistra. Vistra is solely responsible for its portion of the liability for retiree benefits related to those retirees. As we are not responsible for Vistra’s portion of the plan’s unfunded liability, that amount is not reported on our balance sheet. The establishment of the plan is not expected to have an impact on our financial statements.  See Note 10 to Financial Statements in our 2017 Form 10-K for additional information.  Pension and OPEB Costs  Our net costs related to pension plans and the Oncor OPEB Plans for the three and six months ended June 30, 2018 and 2017 were comprised of the following:   Three Months Ended June 30, Six Months Ended June 30,  2018 2017 2018 2017   Components of net allocated pension costs:  Service cost $ 7 $ 6 $ 14 $ 12  Interest cost 30 33 60 66  Expected return on assets (30) (29) (60) (58)  Amortization of net loss 12 11 24 22  Net pension costs 19 21 38 42  Components of net OPEB costs:  Service cost 2 2 4 4  Interest cost 11 12 22 24  Expected return on assets (2) (2) (4) (4)  Amortization of prior service cost (7) (5) (14) (10)  Amortization of net loss 14 8 28 16  Net OPEB costs 18 15 36 30  Total net pension and OPEB costs 37 36 74 72  Less amounts deferred principally as property or a regulatory asset (18) (25) (35) (51)  Net amounts recognized as expense $ 19 $ 11 $ 39 $ 21  The discount rates reflected in net pension and OPEB costs in 2018 are 3.53% , 3.72% and 3.73% for the Oncor Retirement Plan, the Vistra Retirement Plan and the Oncor OPEB Plans, respectively. The expected return on pension and OPEB plan assets reflected in the 2018 cost amounts are 5.13% , 4.78% and 6.20% for the Oncor Retirement Plan, the Vistra Retirement Plan and the Oncor OPEB Plans, respectively.  Pension and OPEB Plans Cash Contributions  We made cash contributions to the pension plans and Oncor OPEB Plans of $42 million and $27 million, respectively, during the six months ended June 30, 2018 . We expect to make additional cash contributions to the pension plans and Oncor OPEB Plans of $40 million and $8 million, respectively, during the remainder of 2018. Our aggregate pension plans and Oncor OPEB Plans funding is expected to total approximately $480 million and $175 million, respectively, in the 2018 to 2022 period based on the latest actuarial projections.

Related-Party Transactions

Related-Party Transactions	6 Months Ended
	Jun. 30, 2018
Related-Party Transactions [Abstract]
RELATED-PARTY TRANSACTIONS	11. RELATED-PARTY TRANSACTIONS  The following represent our significant related-party transactions at June 30, 2018 . As a result of the Sempra Acquisition, Sempra became a related party and the Sponsor Group ceased to be a related party as of March 9, 2018. See Note 2 for information regarding the Sempra Acquisition.  · We are not a member of another entity’s consolidated tax group, but our owners’ federal income tax return s include their portion of our results. Under the terms of a tax sharing agreement among us, Oncor Holdings, Texas Transmis sion, Investment LLC a nd STH (as successor to EFH Corp.) , we are generally obligated to make payments to our owners , pro rata in accordance with their respective membership interests, in an aggregate amount that is substantially equal to the amount of federal income taxes that we would have been required to pay if we were filing our own corporate income tax return. STH will file a combined Texas Margin tax return which includes our results and our share of Texas margin tax payments, which are accounted for as income taxes and calculated as if we were filing our own return. See discussion in Note 1 to Financial Statements in our 2017 Form 10-K under “Income Taxes.” Under the “in lieu of” tax concept, all in lieu of tax assets and tax liabilities represent amounts that will eventually be settled with our members. In the event such amounts are not paid under the tax sharing agreement, it is probable that this regulatory liability will continue to be included in Oncor’s rate setting processes.  Amounts payable to (receivable from) members related to income taxes under the tax sharing agreement and reported on our balance sheet consisted of the following:   At June 30, 2018 At December 31, 2017  STH Texas Transmission Total EFH Corp. Texas Transmission Total   Federal income taxes payable (receivable) $ (3) $ (1) $ (4) $ (21) $ (5) $ (26)  Texas margin taxes payable 13 - 13 21 - 21  Net payable (receivable) $ 10 $ (1) $ 9 $ - $ (5) $ (5)  Cash payments made to (received from) members related to income taxes consisted of the following:   Six Months Ended June 30, 2018 Six Months Ended June 30, 2017  STH EFH Corp. Texas Transmission Total EFH Corp. Texas Transmission Total   Federal income taxes $ 29 $ (19) $ 2 $ 12 $ (102) $ (12) $ (114)  Texas margin taxes 19 - - 19 18 - 18  Total payments (receipts) $ 48 $ (19) $ 2 $ 31 $ (84) $ (12) $ (96)  · Related parties of the Sponsor Group have (1) sold, acquired or participated in the offerings of our debt or debt securities in open market transactions or through loan syndications, and (2) performed various financial advisory, dealer, commercial banking and investment banking services for us and certain of our affiliates for which they have received or will receive customary fees and expenses .  As of March 8, 2018, approximately 16% of the equity in an existing vendor of the company was owned by a member of the Sponsor Group. During 2018 and 2017, this vendor performed transmission and distribution system construction and maintenance services for us. Cash payments were made for such services to this vendor and/or its subsidiaries totaling $35 million dollars for the year-to-date period ended March 8, 2018, of which approximately $33 million was capitalized and $2 million was recorded as an operation and maintenance expense. See Note 9 for information regarding distributions to and capital contributions from members .

Supplementary Financial Informa

Supplementary Financial Information	6 Months Ended
	Jun. 30, 2018
Supplementary Financial Information [Abstract]
SUPPLEMENTARY FINANCIAL INFORMATION	1 2 . SUPPLEMENTARY FINANCIAL INFORMATION  Other Income and ( Deductions )   Three Months Ended June 30, Six Months Ended June 30,  2018 2017 2018 2017   Professional fees $ (2) $ (3) (4) (8)  Sempra Acquisition related costs - - (16) -  Recoverable Pension and OPEB - non-service costs (a) (13) (8) (27) (15)  Other, including interest income (3) - (3) 1  Total other income and (deductions) - net $ (18) $ (11) $ (50) $ (22) ____________ (a) The prior periods have been adjusted to present non-service costs as a non-operating cost pursuant to ASU 2017-07. See Note 1 for additional information.  Interest Expense and Related Charges   Three Months Ended June 30, Six Months Ended June 30,  2018 2017 2018 2017   Interest $ 89 $ 88 $ 178 $ 174  Amortization of debt issuance costs and discounts 2 - 3 1  Less allowance for funds used during construction – capitalized interest portion (4) (3) (6) (5)  Total interest expense and related charges $ 87 $ 85 $ 175 $ 170  Trade Accounts and Other Receivables  Trade accounts and other receivables reported on our balance sheet consist ed of the following:   At June 30, At December 31,  2018 2017   Gross trade accounts and other receivables $ 690 $ 638  Allowance for uncollectible accounts (4) (3)  Trade accounts receivable – net $ 686 $ 635  At June 30, 2018 , REP subsidiaries of our two largest counterparties represented approximately 15% and 12% of the trade accounts receivable balance and at December 31, 2017, represented approximately 12% and 10% of the trade accounts receivable balance.  Under a PUCT rule relating to the Certification of Retail Electric Providers, write-offs of uncollectible amounts owed by nonaffiliated REPs are deferred as a regulatory asset.  Investments and Other Property  Investments and other property reported on our balance sheet consist ed of the following:   At June 30, At December 31,  2018 2017   Assets related to employee benefit plans, including employee savings programs $ 108 $ 111  Land and other investments 10 2  Total investments and other property $ 118 $ 113  Property, Plant and Equipment  Property, plant and equipment reported on our balance sheet consist ed of the following:   At June 30, At December 31,  2018 2017   Total assets in service $ 22,381 $ 21,717  Less accumulated depreciation 7,408 7,255  Net of accumulated depreciation 14,973 14,462  Construction work in progress 512 402  Held for future use 15 15  Property, plant and equipment – net $ 15,500 $ 14,879  Intangible Assets  Intangible assets (other than goodwill) reported on our balance sheet as part of property, plant and equipment consisted of the following:   At June 30, 2018 At December 31, 2017  Gross Gross  Carrying Accumulated Carrying Accumulated  Amount Amortization Net Amount Amortization Net   Identifiable intangible assets subject to amortization:  Land easements $ 454 $ 98 $ 356 $ 453 $ 96 $ 357  Capitalized software 743 363 380 679 339 340  Total $ 1,197 $ 461 $ 736 $ 1,132 $ 435 $ 697  A ggregate amortization expense for intangible assets totaled $14 million and $15 million for the three months ended June 30, 2018 and 2017, respectively , and $26 million and $29 million for the six months ended June 30, 2018 and 2017, respectively. The estimated aggregate amortization expense for each of the next five fiscal years is as follows:   Year Amortization Expense  2018 $ 51  2019 50  2020 49  2021 49  2022 49  At both June 30, 2018 and December 31, 2017, goodwill totaling $ 4.1 billion was reported on our balance sheet. None of this goodwill is being deducted for tax purposes.  Employee Benefit Obligations and Other  Employee benefit obligations and other reported on our balance sheet consisted of the following:   At June 30, At December 31,  2018 2017   Retirement plans and other employee benefits $ 1,983 $ 2,035  Investment tax credits 9 10  Other 69 57  Total employee benefit obligations and other $ 2,061 $ 2,102  Supplemental Cash Flow Information   Six Months Ended June 30,  2018 2017   Cash payments (receipts) related to:  Interest $ 172 $ 170  Less capitalized interest (6) (5)  Interest payments (net of amounts capitalized) $ 166 $ 165  Amount in lieu of income taxes (a):  Federal $ 12 $ (114)  State 19 18  Total payments (receipts) in lieu of income taxes $ 31 $ (96)   Noncash construction expenditures (b) $ 121 $ 132 ____________ (a) See Note 1 1 for income tax related detail. (b) Represents end-of-period accruals.

Business and Significant Acco19

Business and Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2018
Business and Significant Accounting Policies [Abstract]
Description Of Business	Description of Business  References in this report to “we,” “our,” “us” and “the company” are to Oncor. See “Glossary” for definition of terms and abbreviations.  We are a regulated electricity transmission and distribution company principally engaged in providing delivery services to REPs that sell power in the north-central, eastern and western parts of Texas. We are a direct, majority-owned subsidiary of Oncor Holdings, which is a direct, wholly-owned subsidiary of STIH, a direct wholly-owned subsidiary of STH. In connection with the Sempra Acquisition, on March 9, 2018, STH became an indirect wholly- owned subsidiary of Sempra. Oncor Holdings owns 80.25% of our membership interests and Texas Transmission owns 19.75% of our membership interests. We are managed as an integrated business; consequently, there are no separate reportable business segments.  Various “ring-fencing” measures that had been taken to enhance our credit quality and the separateness between the Oncor Ring-Fenced Entities and its majority owner (formerly the Texas Holdings Group and now Sempra) continue to remain in effect after the Sempra Acquisition. These measures serve to mitigate our and Oncor Holdings’ credit exposure to Sempra and to reduce the risk that our assets and liabilities or those of Oncor Holdings would be substantively consolidated with the assets and liabilities of Sempra in connection with a bankruptcy of one or more Sempra entities. Such measures include, among other things: the 19.75% equity interest held by Texas Transmission; maintenance of separate books and records for the Oncor Ring-Fenced Entities; our board of directors being comprised of a majority of independent directors; and prohibitions on the Oncor Ring-Fenced Entities providing credit support to or receiving credit support from Sempra entities . The assets and liabilities of the Oncor Ring-Fenced Entities are separate and distinct from those of Sempra. None of the assets of the Oncor Ring-Fenced Entities are available to satisfy the debt or contractual obligations of Sempra entities . We do not bear any liability for debt or contractual obligations of Sempra, and vice versa. Accordingly, our operations are conducted, and our cash flows are managed, independently from Sempra. For more information on ring-fencing measures, see Note 2.
EFH Bankruptcy Proceedings And Change In Indirect Ownership Of Oncor	EFH Bankruptcy Proceedings and Change in Indirect Ownership of Oncor  In April 2014, EFH Corp. and the substantial majority of its direct and indirect subsidiaries at the time, including EFIH, EFCH and TCEH, commenced proceedings under Chapter 11 of the U.S. Bankruptcy Code. The Oncor Ring-Fenced Entities were not parties to the EFH Bankruptcy Proceedings. In connection with the plans of reorganization in the EFH Bankruptcy Proceedings, on March 9, 2018, Sempra acquired the 80.03% of Oncor’s membership interests owned indirectly by EFH Corp. and EFIH (Sempra Acquisition). See Note 2 for further information.
Basis Of Presentation	Basis of Presentation  These unaudited condensed financial statements should be read in conjunction with the audited financial statements and related notes included in the 2017 Form 10-K. In the opinion of Oncor management, all adjustments (consisting of normal recurring accruals) necessary for a fair presentation of the results of operations and financial position have been made. All intercompany items and transactions have been eliminated in consolidation. The results of operations for an interim period may not give a true indication of results for a full year due to seasonality. All dollar amounts in the financial statements and tables in the notes are stated in millions of U.S. dollars unless otherwise indicated.
Use Of Estimates	Use of Estimates  Preparation of our financial statements requires management to make estimates and assumptions about future events that affect the reporting of assets and liabilities at the balance sheet dates and the reported amounts of revenue and expense, including fair value measurements. In the event estimates and/or assumptions prove to be different from actual amounts, adjustments are made in subsequent periods to reflect more current information. No material adjustments were made to previous estimates or assumptions during the current period.
Changes In Accounting Standards	Changes in Accounting Standards  Since May 2014, the Financial Accounting Standards Board (FASB) has issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers , along with other supplemental guidance (together, Topic 606). Topic 606 introduced new, increased requirements for disclosure of revenue in financial statements and guidance intended to eliminate inconsistencies in the recognition of revenue. We adopted Topic 606 effective January 1, 2018 using the modified retrospective approach and elected the practical expedient available that allows an entity to recognize revenue in the amount to which the entity has the right to invoice related to performance completed to date. Our r evenues are generally recognized when the underlying service has been provided in an amount prescribed by the related tariff. The new guidance did not change this pattern of recognition and therefore the adoption did not have a material effect on our reported results of operations, financial position or cash flows. Topic 606 also requires the separate presentation of “alternative revenue program” revenues on the income statement. We anticipate less than $20 million annually in alternative revenue program revenues related to our energy efficiency program and will disclose such activity in the notes to financial statements. See Note 4 for additional disclosures about revenues from contracts with customers.  In February 2016, the FASB issued ASU 2016-02 which created FASB Topic 842, Leases (Topic 842). Topic 842 amends previous GAAP to require the balance sheet recognition of substantially all lease assets and liabilities, including operating leases. Operating lease liabilities are not classified as debt for GAAP purposes under Topic 842 and are not treated as debt for regulatory purposes. Under current standards , all of Oncor’s existing leases meet the definition of an operating lease. Under the new rules, the recognition of any finance leases (currently known as capital leases) on the balance sheet would be classified as debt for GAAP purposes and are expected to be defined as debt for our regulatory capital structure purposes (see Note 9 for details) similar to the current capital lease treatment. We will be required to adopt Topic 842 by January 1, 2019 and we expect to use certain practical expedients and policy elections available under the guidance including a practical expedient to not assess whether existing land easements that were not previously accounted for as leases are or contain a lease under Topic 842, a n adoption method to not restate comparative periods and a policy election to forego the application of Topic 842 recognition requirements to short-term leases. The initial adoption of Topic 842 will affect our balance sheet, as our contracts for office space and fleet vehicles are currently clas sified as operating leases. Subsequent to adoption, to the extent Oncor enters into finance leases, its credit facility cov enants and capitalization ratios could be impacted. We continue to evaluate our contracts for proper treatment under the new standards and the estimated impact on our financial statements.  In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost , an amendment to Topic 715, Compensation – Retirement Benefits . ASU 2017-07 requires the non-service cost components of net retirement benefit plan costs be presented as non-operating in the income statement. In addition, only the service cost component of net retirement benefit plan cost is eligible for capitalization as part of inventory or property, plant and equipment. We adopted ASU 2017-07 on January 1, 2018. The presentation of costs is required to be applied on a retrospective basis while the capitalization eligibility requirement is applied on a prospective basis. The guidance allows a practical expedient that permits use of previously disclosed service costs and non-service costs of the Pension and OPEB Plans in the comparative periods as appropriate estimates when recasting the presentation of these costs in the income statements. We have elected this practical expedient. For cash flow purposes on a prospective basis, non-service costs will be reflected as a reduction to operating cash flows, offset by lower cash used in investing activities (lower capital expenditures). The new guidance did not have a material effect on our results of operations, financial position or net change in total cash flows and we do not expect the guidance to have a material effect on our rate-making process. For the three - and six- month periods ended June 30 , 2017, the adoption of ASU 2017-07 resulted in a reclassification of $8 million and $15 million from operation and maintenance expense to other income and (deductions), respectively, and a corresponding reclassification of $3 million and $6 million, respectively, from provision in lieu of income taxes to nonoperating pr ovision in lieu of income taxes. For the years 2015, 2016 and 2017, the reclassification amounts are $ 28 million, $28 million and $ 31 million from operation and maintenance expense to other income and (deductions), respectively, and a corresponding reclassification of $ 10 million, $10 million and $11 million, respectively, from provision in lieu of income taxes to nonoperating pr ovision in lieu of income taxes.  In February 2018, the FASB issued ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (ASU 2018-02). ASU 2018-02 allows a reclassification from accumulated other comprehensive income (AOCI) to capital accounts for stranded tax effects resulting from the TCJA. Under ASU 2018-02, an entity will be required to provide certain disclosures regarding stranded tax effects, including its accounting policy related to releasing the income tax effects from AOCI. We estimate our stranded tax effects in AOCI to be approximately $22 million. ASU 2018-02 can be applied either as of the beginning of the period of adoption or retrospectively as of the date of enactment of the TCJA and to each period in which the effect of the TCJA is recognized. ASU 2018-02 is effective for our 2019 annual reporting p eriod, including interim periods therein, with early adoption permitted. We have not yet selected the adoption method or the year in which we will adopt the standard.

Revenues (Tables)

Revenues (Tables)	6 Months Ended
	Jun. 30, 2018
Revenues [Abstract]
Disaggregation Of Revenues	  Three Months Ended June 30, Six Months Ended June 30,  Operating revenues 2018 2018  Revenues contributing to earnings:  Distribution base revenues $ 529 $ 1,036  Transmission base revenues (TCOS revenues)  Billed to third-party wholesale customers 141 266  Billed to REPs serving Oncor distribution customers, through TCRF 79 157  Total transmission base revenues 220 423  Other miscellaneous revenues 16 31  Total revenues contributing to earnings 765 1,490   Revenues collected for pass-through expenses:  TCRF - third-party wholesale transmission service 238 483  EECRF and other regulatory charges 18 38  Revenues collected for pass-through expenses 256 521   Total operating revenues $ 1,021 $ 2,011 

Regulatory Assets and Liabili21

Regulatory Assets and Liabilities (Tables)	6 Months Ended
	Jun. 30, 2018
Regulatory Assets and Liabilities [Abstract]
Components Of Regulatory Assets And Liabilities	  Remaining Rate Recovery/Amortization Period at Carrying Amount At  June 30, 2018 June 30, 2018 December 31, 2017   Regulatory assets:  Employee retirement costs being amortized 10 years $ 314 $ 331  Unrecovered employee retirement costs incurred since the last rate review period (a) To be determined 30 30  Employee retirement liability (a)(b)(c) To be determined 818 854  Employee retirement plans - non-service costs Lives of related assets 22 -  Self-insurance reserve (primarily storm recovery costs) being amortized 10 years 373 394  Unrecovered self-insurance reserve incurred since the last rate review period (a) To be determined 50 49  Securities reacquisition costs Lives of related debt 11 12  Deferred conventional meter and metering facilities depreciation 3 years 47 57  Under-recovered AMS costs 10 years 195 206  Excess deferred income taxes To be determined 202 197  Energy efficiency performance bonus (b) 1 year or less 6 12  Other regulatory assets Various 25 38  Total regulatory assets 2,093 2,180   Regulatory liabilities:  Estimated net removal costs Lives of related assets 992 954  Excess deferred income taxes To be determined 1,794 1,789  Federal income taxes - over-collected due to TCJA rate change To be determined 49 -  Over-recovered wholesale transmission service expense (b) 1 year or less 16 47  Other regulatory liabilities Various 27 17  Total regulatory liabilities 2,878 2,807  Net regulatory assets (liabilities) $ (785) $ (627) ____________ (a) Recovery is specifically authorized by statute or by the PUCT, subject to reasonableness review. (b) Not earning a return in the regulatory rate-setting process. (c) Represents unfunded liabilities recorded in accordance with pension and OPEB accounting standards.

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	6 Months Ended
	Jun. 30, 2018
Short-Term Borrowings [Abstract]
Schedule Of Short-Term Borrowings	  At June 30, At December 31,  2018 2017  Total borrowing capacity $ 2,000 $ 2,000  Commercial paper outstanding (a) (1,296) -  Credit facility outstanding (b) - (950)  Letters of credit outstanding (c) (9) (9)  Available unused credit $ 695 $ 1,041 ____________ a) The weighted average interest rate for commercial paper at June 30, 2018 was 2.49% . . b) The weighted average interest rate for the credit facility at December 31, 2017 was 2.62% . c) Interest rates on outstanding letters of credit at June 30, 2018 and December 31, 207 were 1.200% and 1.325% , respectively, based on our credit ratings.

Long-Term Debt (Tables)

Long-Term Debt (Tables)	6 Months Ended
	Jun. 30, 2018
Long-Term Debt [Abstract]
Schedule Of Long-Term Debt	  June 30, December 31,  2018 2017   Secured:  6.800% Fixed Senior Notes due September 1, 2018 $ 550 $ 550  2.150% Fixed Senior Notes due June 1, 2019 250 250  5.750% Fixed Senior Notes due September 30, 2020 126 126  4.100% Fixed Senior Notes due June 1, 2022 400 400  7.000% Fixed Debentures due September 1, 2022 800 800  2.950% Fixed Senior Notes due April 1, 2025 350 350  7.000% Fixed Senior Notes due May 1, 2032 500 500  7.250% Fixed Senior Notes due January 15, 2033 350 350  7.500% Fixed Senior Notes due September 1, 2038 300 300  5.250% Fixed Senior Notes due September 30, 2040 475 475  4.550% Fixed Senior Notes due December 1, 2041 400 400  5.300% Fixed Senior Notes due June 1, 2042 500 500  3.750% Fixed Senior Notes due April 1, 2045 550 550  3.800% Fixed Senior Notes due September 30, 2047 325 325  Secured long-term debt 5,876 5,876  Unsecured:  Term loan credit agreement due no later than March 26, 2019 131 275  Total long-term debt 6,007 6,151  Unamortized discount and debt issuance costs (32) (34)  Less amount due currently (931) (550)  Long-term debt, less amounts due currently $ 5,044 $ 5,567 

Membership Interests (Tables)

Membership Interests (Tables)	6 Months Ended
	Jun. 30, 2018
Membership Interests [Abstract]
Schedule Of Changes To Membership Interests	  Capital Accounts Accumulated Other Comprehensive Income (Loss) Total Membership Interests   Balance at December 31, 2017 $ 8,004 $ (101) $ 7,903  Net income 232 - 232  Capital contributions 144 - 144  Defined benefit pension plans (net of tax) - 2 2  Balance at June 30, 2018 $ 8,380 $ (99) $ 8,281   Balance at December 31, 2016 $ 7,822 $ (111) $ 7,711  Net income 185 - 185  Distributions (172) - (172)  Net effects of cash flow hedges (net of tax) - 1 1  Defined benefit pension plans (net of tax) - 1 1  Balance at June 30, 2017 $ 7,835 $ (109) $ 7,726 
Schedule Of Changes To Accumulated Other Comprehensive Income (Loss)	  Cash Flow Hedges – Interest Rate Swap Defined Benefit Pension and OPEB Plans Accumulated Other Comprehensive Income (Loss)   Balance at December 31, 2017 $ (18) $ (83) $ (101)  Defined benefit pension plans (net of tax) - 2 2  Amounts reclassified from accumulated other comprehensive income (loss) and reported in interest expense and related charges - - -  Balance at June 30, 2018 $ (18) $ (81) $ (99)   Balance at December 31, 2016 $ (20) $ (91) $ (111)  Defined benefit pension plans (net of tax) - 1 1  Amounts reclassified from accumulated other comprehensive income (loss) and reported in interest expense and related charges 1 - 1  Balance at June 30, 2017 $ (19) $ (90) $ (109) 

Pension and OPEB Plans (Tables)

Pension and OPEB Plans (Tables)	6 Months Ended
	Jun. 30, 2018
Pension And OPEB Plans [Abstract]
Schedule Of Pension And OPEB Plan Costs	  Three Months Ended June 30, Six Months Ended June 30,  2018 2017 2018 2017   Components of net allocated pension costs:  Service cost $ 7 $ 6 $ 14 $ 12  Interest cost 30 33 60 66  Expected return on assets (30) (29) (60) (58)  Amortization of net loss 12 11 24 22  Net pension costs 19 21 38 42  Components of net OPEB costs:  Service cost 2 2 4 4  Interest cost 11 12 22 24  Expected return on assets (2) (2) (4) (4)  Amortization of prior service cost (7) (5) (14) (10)  Amortization of net loss 14 8 28 16  Net OPEB costs 18 15 36 30  Total net pension and OPEB costs 37 36 74 72  Less amounts deferred principally as property or a regulatory asset (18) (25) (35) (51)  Net amounts recognized as expense $ 19 $ 11 $ 39 $ 21 

Related-Party Transactions (Tab

Related-Party Transactions (Tables)	6 Months Ended
	Jun. 30, 2018
Related-Party Transactions [Abstract]
Schedule Of Trade Accounts And Other Receivables From Related Parties	  At June 30, 2018 At December 31, 2017  STH Texas Transmission Total EFH Corp. Texas Transmission Total   Federal income taxes payable (receivable) $ (3) $ (1) $ (4) $ (21) $ (5) $ (26)  Texas margin taxes payable 13 - 13 21 - 21  Net payable (receivable) $ 10 $ (1) $ 9 $ - $ (5) $ (5) 
Schedule Of Related Party Transactions	  Six Months Ended June 30, 2018 Six Months Ended June 30, 2017  STH EFH Corp. Texas Transmission Total EFH Corp. Texas Transmission Total   Federal income taxes $ 29 $ (19) $ 2 $ 12 $ (102) $ (12) $ (114)  Texas margin taxes 19 - - 19 18 - 18  Total payments (receipts) $ 48 $ (19) $ 2 $ 31 $ (84) $ (12) $ (96) 

Supplementary Financial Infor27

Supplementary Financial Information (Tables)	6 Months Ended
	Jun. 30, 2018
Supplementary Financial Information [Abstract]
Schedule Of Other Income And (Deductions)	  Three Months Ended June 30, Six Months Ended June 30,  2018 2017 2018 2017   Professional fees $ (2) $ (3) (4) (8)  Sempra Acquisition related costs - - (16) -  Recoverable Pension and OPEB - non-service costs (a) (13) (8) (27) (15)  Other, including interest income (3) - (3) 1  Total other income and (deductions) - net $ (18) $ (11) $ (50) $ (22) ____________ (a) The prior periods have been adjusted to present non-service costs as a non-operating cost pursuant to ASU 2017-07. See Note 1 for additional information.
Schedule Of Interest Expense And Related Charges	  Three Months Ended June 30, Six Months Ended June 30,  2018 2017 2018 2017   Interest $ 89 $ 88 $ 178 $ 174  Amortization of debt issuance costs and discounts 2 - 3 1  Less allowance for funds used during construction – capitalized interest portion (4) (3) (6) (5)  Total interest expense and related charges $ 87 $ 85 $ 175 $ 170 
Schedule Of Trade Accounts And Other Receivables	  At June 30, At December 31,  2018 2017   Gross trade accounts and other receivables $ 690 $ 638  Allowance for uncollectible accounts (4) (3)  Trade accounts receivable – net $ 686 $ 635 
Summary of Investments And Other Property	  At June 30, At December 31,  2018 2017   Assets related to employee benefit plans, including employee savings programs $ 108 $ 111  Land and other investments 10 2  Total investments and other property $ 118 $ 113 
Schedule Of Property, Plant And Equipment	  At June 30, At December 31,  2018 2017   Total assets in service $ 22,381 $ 21,717  Less accumulated depreciation 7,408 7,255  Net of accumulated depreciation 14,973 14,462  Construction work in progress 512 402  Held for future use 15 15  Property, plant and equipment – net $ 15,500 $ 14,879 
Schedule Of Intangible Assets	  At June 30, 2018 At December 31, 2017  Gross Gross  Carrying Accumulated Carrying Accumulated  Amount Amortization Net Amount Amortization Net   Identifiable intangible assets subject to amortization:  Land easements $ 454 $ 98 $ 356 $ 453 $ 96 $ 357  Capitalized software 743 363 380 679 339 340  Total $ 1,197 $ 461 $ 736 $ 1,132 $ 435 $ 697 
Schedule Of Estimated Aggregate Amortization Expenses	  Year Amortization Expense  2018 $ 51  2019 50  2020 49  2021 49  2022 49 
Schedule Of Employee Benefit Obligations And Other	  At June 30, At December 31,  2018 2017   Retirement plans and other employee benefits $ 1,983 $ 2,035  Investment tax credits 9 10  Other 69 57  Total employee benefit obligations and other $ 2,061 $ 2,102 
Schedule Of Supplemental Cash Flow Information	  Six Months Ended June 30,  2018 2017   Cash payments (receipts) related to:  Interest $ 172 $ 170  Less capitalized interest (6) (5)  Interest payments (net of amounts capitalized) $ 166 $ 165  Amount in lieu of income taxes (a):  Federal $ 12 $ (114)  State 19 18  Total payments (receipts) in lieu of income taxes $ 31 $ (96)   Noncash construction expenditures (b) $ 121 $ 132 ____________ (a) See Note 1 1 for income tax related detail. (b) Represents end-of-period accruals.

Business and Significant Acco28

Business and Significant Accounting Policies (Narrative) (Details) $ in Millions	1 Months Ended	3 Months Ended			6 Months Ended
	Nov. 30, 2008	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	[1]	Jun. 30, 2018USD ($)segmententity	Jun. 30, 2017USD ($)	Mar. 09, 2018
Business And Significant Accounting Polices [Line Items]
Number of reportable business segments | segment					0
Number of entities that would possibly be bankrupt | entity					1
Revenues		$ 1,021	$ 964		$ 2,011	$ 1,899
Percentage of equity interest sold in the event of bankruptcy	19.75%
Accounting Standards Update 2017-07 [Member]
Business And Significant Accounting Polices [Line Items]
Reclassification from operation and maintenance expense to other income and (deductions)		8				15
Increase in provision in lieu of income taxes and decrease in non-operating provision in lieu of income taxes		$ 3				$ 6
Accounting Standards Update 2018-02 [Member]
Business And Significant Accounting Polices [Line Items]
Reclassification from AOCI to membership interests for stranded tax effects					$ 22
Oncor Holdings [Member] | Oncor [Member]
Business And Significant Accounting Polices [Line Items]
Ownership interests acquired							0.22%
Texas Transmission [Member]
Business And Significant Accounting Polices [Line Items]
Percentage of membership interest owned by non-controlling owners		19.75%			19.75%
Sempra Energy [Member] | Oncor [Member]
Business And Significant Accounting Polices [Line Items]
Ownership interests acquired							80.03%
Maximum [Member] | Accounting Standards Update 2014-09 [Member]
Business And Significant Accounting Polices [Line Items]
Alternative revenue program					$ 20
[1]	As adjusted for the retrospective adoption of ASU 2017-07, as discussed in Note 1.

EFH Bankruptcy Proceedings an29

EFH Bankruptcy Proceedings and Change in Indirect Ownership of Oncor (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	Mar. 09, 2018	Nov. 27, 2017	Jun. 30, 2018	Apr. 23, 2018
Bankruptcy [Line Items]
Regulatory capitalization ratio, debt	57.50%	57.50%	56.75%
Regulatory capitalization ratio, equity	42.50%	42.50%	43.25%
Percent of savings for bill credits			90.00%
Texas Holdings Group [Member]
Bankruptcy [Line Items]
Percentage of membership interest owned by non-controlling owners	19.75%
Oncor [Member] | Sempra Energy [Member]
Bankruptcy [Line Items]
Purchase price	$ 9,450
Percent increase or decrease for disinterested directors to approve any budget			10.00%
Minimum aggregate capital expenditures			$ 7,500
Number of days for proportionate share of aggregate equity investment			60 days
Transaction or transition costs				$ 117
Ownership interests acquired	80.03%
Oncor [Member] | Oncor Holdings [Member]
Bankruptcy [Line Items]
Ownership interests acquired	0.22%
OMI Agreement [Member] | Oncor [Member] | Sempra Energy [Member]
Bankruptcy [Line Items]
Cash paid	$ 26
Share price	$ 18.60
OMI Agreement [Member] | Oncor [Member] | Oncor Holdings [Member]
Bankruptcy [Line Items]
Shares acquired	1,396,008
Minimum [Member] | Oncor [Member] | Sempra Energy [Member]
Bankruptcy [Line Items]
Ownership percentage			51.00%
Required time for holding owndership interests			5 years

Regulatory Matters (Narrative)

Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	Jul. 01, 2018	Jun. 30, 2018	Dec. 31, 2017	Jun. 13, 2018	Apr. 05, 2018
Public Utilities, General Disclosures [Line Items]
DCRF increase				$ 15	$ 19
U.S. federal statutory rate		21.00%	35.00%
Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Requested base rate revenue	$ 15
Increase in revenue from incorporating new corporate tax rate	181
Decrease in current taxes	144
Increase (decrease) in liability for deferred income taxes	$ 37

Revenues (Narrative) (Details)

Revenues (Narrative) (Details) - item	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Number of REPS		90
REP Subsidiary One [Member] | Sales Revenue, Net [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	20.00%	22.00%
REP Subsidiary Two [Member] | Sales Revenue, Net [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	17.00%	18.00%

Revenues (Disaggregation Of Rev

Revenues (Disaggregation Of Revenues) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	$ 765	$ 1,490
Revenues collected for pass-through expenses	256	521
Total operating revenues	1,021	2,011
Distribution Base Revenues [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	529	1,036
Transmission Base Revenues (TCOS Revenues) [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	220	423
Transmission Base Revenues (TCOS Revenues) [Member] | Third-Party Wholesale Customers [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	141	266
Transmission Base Revenues (TCOS Revenues) [Member] | REPS Serving Oncor Distribution Customers, Through TCRF [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	79	157
Other Miscellaneous Revenues [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	16	31
TCRF - Third-party Wholesale Transmission Service [Member]
Disaggregation of Revenue [Line Items]
Revenues collected for pass-through expenses	238	483
EECRF And Other Regulatory Charges [Member]
Disaggregation of Revenue [Line Items]
Revenues collected for pass-through expenses	$ 18	$ 38

Regulatory Assets And Liabili33

Regulatory Assets And Liabilities (Components Of Regulatory Assets And Liabilities) (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2018	Dec. 31, 2017
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets		$ 2,093	$ 2,180
Carrying Amount, Regulatory Liabilities		2,878	2,807
Net regulatory assets (liabilities)		$ (785)	(627)
Estimated Net Removal Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		Lives of related assets
Carrying Amount, Regulatory Liabilities		$ 992	954
Excess Deferred Income Taxes [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		To be determined
Carrying Amount, Regulatory Liabilities		$ 1,794	1,789
Federal Income Taxes - Over-collected Due To TCJA Rate Change [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		To be determined
Carrying Amount, Regulatory Liabilities		$ 49
Over-Recovered Wholesale Transmission Service Expense [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	[1]	1 year or less
Carrying Amount, Regulatory Liabilities	[1]	$ 16	47
Other Regulatory Liabilities [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		Various
Carrying Amount, Regulatory Liabilities		$ 27	17
Employee Retirement Costs Being Amortized [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		10 years
Carrying Amount, Regulatory Assets		$ 314	331
Unrecovered Employee Retirement Costs Incurred Since The Last Rate Review Period [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	[2]	To be determined
Carrying Amount, Regulatory Assets	[2]	$ 30	30
Employee Retirement Liability [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	[1],[2],[3]	To be determined
Carrying Amount, Regulatory Assets	[1],[2],[3]	$ 818	854
Employee Retirement Plans - Non-service Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		Lives of related assets
Carrying Amount, Regulatory Assets		$ 22
Self-Insurance Reserve (Primarily Storm Recovery Costs) Being Amortized [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		10 years
Carrying Amount, Regulatory Assets		$ 373	394
Unrecovered Self-Insurance Reserve Incurred Since The Last Rate Review Period [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	[2]	To be determined
Carrying Amount, Regulatory Assets	[2]	$ 50	49
Securities Reacquisition Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		Lives of related debt
Carrying Amount, Regulatory Assets		$ 11	12
Deferred Conventional Meter And Metering Facilities Depreciation [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		3 years
Carrying Amount, Regulatory Assets		$ 47	57
Under-recovered AMS Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		10 years
Carrying Amount, Regulatory Assets		$ 195	206
Excess Deferred Income Taxes [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		To be determined
Carrying Amount, Regulatory Assets		$ 202	197
Energy Efficiency Performance Bonus [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	[1]	1 year or less
Carrying Amount, Regulatory Assets	[1]	$ 6	12
Other Regulatory Assets [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period		Various
Carrying Amount, Regulatory Assets		$ 25	$ 38
[1]	Not earning a return in the regulatory rate-setting process.
[2]	Recovery is specifically authorized by statute or by the PUCT, subject to reasonableness review.
[3]	Represents unfunded liabilities recorded in accordance with pension and OPEB accounting standards.

Short-Term Borrowings (Narrativ

Short-Term Borrowings (Narrative) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018USD ($)contract	Dec. 31, 2017USD ($)
Line of Credit Facility [Line Items]
Borrowing capacity available under the credit facility	$ 2,000	$ 2,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 2,000
Number of revolving credit facilities extension options | contract	2
Extension period for revolving line of credit	1 year
Credit facility, term	5 years
Expiration of revolving credit facility	Nov. 1, 2022
Commitment fee	0.10%
Revolving Credit Facility [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Additional increase in borrowing capacity amount	$ 400
Commitment fee	0.225%
Debt-to-capitalization ratio	1
Revolving Credit Facility [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Additional increase in borrowing capacity amount	$ 100
Commitment fee	0.075%
Debt-to-capitalization ratio	0.65
Commercial Paper [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 2,000
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	1.00%
London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	1.50%
London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	0.875%
Federal Funds Effective Rate [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	0.50%
One-Month London Interbank Offered Rate [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	1.00%
One-Month London Interbank Offered Rate [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	0.50%
One-Month London Interbank Offered Rate [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	0.00%

Short-Term Borrowings (Schedule

Short-Term Borrowings (Schedule Of Short-Term Borrowings) (Details) - USD ($) $ in Millions		Jun. 30, 2018	Dec. 31, 2017
Short-term Debt [Line Items]
Total borrowing capacity		$ 2,000	$ 2,000
Available unused credit		695	1,041
Commercial Paper [Member]
Short-term Debt [Line Items]
Outstanding	[1]	$ (1,296)
Interest Rate		2.49%
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Outstanding	[2]		$ (950)
Interest Rate			2.62%
Letter of Credit [Member]
Short-term Debt [Line Items]
Outstanding	[3]	$ (9)	$ (9)
Interest Rate		1.20%	1.325%
[1]	The weighted average interest rate for commercial paper at June 30, 2018 was 2.49%. .
[2]	The weighted average interest rate for the credit facility at December 31, 2017 was 2.62%.
[3]	Interest rates on outstanding letters of credit at June 30, 2018 and December 31, 207 were 1.200% and 1.325%, respectively, based on our credit ratings.

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Long-Term Debt [Line Items]
Repayments of long-term debt	$ 144
Estimated fair value of our long-term debt including current maturities	6,652	$ 7,153
Carrying amount	$ 5,975	$ 6,117
Secured Debt [Member]
Long-Term Debt [Line Items]
Percentage of fair value of cost of property additions certified to the Deed of Trust collateral agent	85.00%
Available bond credits	$ 3,038
Future debt subject to property additions to the Deed of Trust	$ 2,882

Long-Term Debt (Schedule Of Lon

Long-Term Debt (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total long-term debt	$ 6,007	$ 6,151
Unamortized discount and debt issuance costs	(32)	(34)
Less amount due currently	(931)	(550)
Long-term debt, less amounts due currently	5,044	5,567
Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	5,876	5,876
Unsecured Debt [Member]
Debt Instrument [Line Items]
Term loan	$ 131	$ 275
6.800% Fixed Senior Notes Due September 1, 2018 [Member]
Debt Instrument [Line Items]
Interest percentage	6.80%	6.80%
Due date	Sep. 1, 2018
6.800% Fixed Senior Notes Due September 1, 2018 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 550	$ 550
2.150% Fixed Senior Notes Due June 1, 2019 [Member]
Debt Instrument [Line Items]
Interest percentage	2.15%	2.15%
Due date	Jun. 1, 2019
2.150% Fixed Senior Notes Due June 1, 2019 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 250	$ 250
5.750% Fixed Senior Notes Due September 30, 2020 [Member]
Debt Instrument [Line Items]
Interest percentage	5.75%	5.75%
Due date	Sep. 30, 2020
5.750% Fixed Senior Notes Due September 30, 2020 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 126	$ 126
4.100% Fixed Senior Notes Due June 1, 2022 [Member]
Debt Instrument [Line Items]
Interest percentage	4.10%	4.10%
Due date	Jun. 1, 2022
4.100% Fixed Senior Notes Due June 1, 2022 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 400	$ 400
7.000% Fixed Debentures Due September 1, 2022 [Member]
Debt Instrument [Line Items]
Interest percentage	7.00%	7.00%
Due date	Sep. 1, 2022
7.000% Fixed Debentures Due September 1, 2022 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 800	$ 800
2.950% Fixed Senior Notes Due April 1, 2025 [Member]
Debt Instrument [Line Items]
Interest percentage	2.95%	2.95%
Due date	Apr. 1, 2025
2.950% Fixed Senior Notes Due April 1, 2025 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 350	$ 350
7.000% Fixed Senior Notes Due May 1, 2032 [Member]
Debt Instrument [Line Items]
Interest percentage	7.00%	7.00%
Due date	May 1, 2032
7.000% Fixed Senior Notes Due May 1, 2032 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 500	$ 500
7.250% Fixed Senior Notes Due January 15, 2033 [Member]
Debt Instrument [Line Items]
Interest percentage	7.25%	7.25%
Due date	Jan. 15, 2033
7.250% Fixed Senior Notes Due January 15, 2033 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 350	$ 350
7.500% Fixed Senior Notes Due September 1, 2038 [Member]
Debt Instrument [Line Items]
Interest percentage	7.50%	7.50%
Due date	Sep. 1, 2038
7.500% Fixed Senior Notes Due September 1, 2038 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 300	$ 300
5.250% Fixed Senior Notes Due September 30, 2040 [Member]
Debt Instrument [Line Items]
Interest percentage	5.25%	5.25%
Due date	Sep. 30, 2040
5.250% Fixed Senior Notes Due September 30, 2040 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 475	$ 475
4.550% Fixed Senior Notes Due December 1, 2041 [Member]
Debt Instrument [Line Items]
Interest percentage	4.55%	4.55%
Due date	Dec. 1, 2041
4.550% Fixed Senior Notes Due December 1, 2041 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 400	$ 400
5.300% Fixed Senior Notes Due June 1, 2042 [Member]
Debt Instrument [Line Items]
Interest percentage	5.30%	5.30%
Due date	Jun. 1, 2042
5.300% Fixed Senior Notes Due June 1, 2042 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 500	$ 500
3.750% Fixed Senior Notes Due April 1, 2045 [Member]
Debt Instrument [Line Items]
Interest percentage	3.75%	3.75%
Due date	Apr. 1, 2045
3.750% Fixed Senior Notes Due April 1, 2045 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 550	$ 550
3.800% Fixed Senior Notes Due September 30, 2047 [Member]
Debt Instrument [Line Items]
Interest percentage	3.80%	3.80%
Due date	Sep. 30, 2047
3.800% Fixed Senior Notes Due September 30, 2047 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 325	$ 325
Term Loan Credit Agreement Due No Later Than March 26, 2019 [Member]
Debt Instrument [Line Items]
Due date	Mar. 26, 2019

Membership Interests (Narrative

Membership Interests (Narrative) (Details) - USD ($) $ in Millions	Jul. 25, 2018	Mar. 09, 2018	Nov. 27, 2017	Apr. 30, 2018	Jun. 30, 2018
Subsequent Event [Line Items]
Cash available for distribution under the capital structure restriction					$ 137
Regulatory capitalization ratio, debt		57.50%	57.50%		56.75%
Regulatory capitalization ratio, equity		42.50%	42.50%		43.25%
Members contribution				$ 144	$ 144
Subsequent Event [Member]
Subsequent Event [Line Items]
Contingent equity distribution	$ 30

Membership Interests (Schedule

Membership Interests (Schedule Of Changes To Membership Interests) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			6 Months Ended
	Apr. 30, 2018	Jun. 30, 2018	Jun. 30, 2017		Jun. 30, 2018	Jun. 30, 2017
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Balance					$ 7,903	$ 7,711
Net income		$ 143	$ 112	[1]	232	185
Capital contributions	$ 144				144
Distributions						(172)
Net effects of cash flow hedges (net of tax)						1
Defined benefit pension plans (net of tax)		1	1		2	1
Balance		8,281	7,726		8,281	7,726
Capital Accounts [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Balance					8,004	7,822
Net income					232	185
Capital contributions					144
Distributions						(172)
Net effects of cash flow hedges (net of tax)
Defined benefit pension plans (net of tax)
Balance		8,380	7,835		8,380	7,835
Accumulated Other Comprehensive Income (Loss) [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Balance					(101)	(111)
Net income
Capital contributions
Distributions
Net effects of cash flow hedges (net of tax)						1
Defined benefit pension plans (net of tax)					2	1
Balance		$ (99)	$ (109)		$ (99)	$ (109)
[1]	As adjusted for the retrospective adoption of ASU 2017-07, as discussed in Note 1.

Membership Interests (Schedul40

Membership Interests (Schedule Of Changes To Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (101)
Balance at end of period	(99)
Cash Flow Hedges - Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(18)	$ (20)
Defined benefit pension plans (net of tax)
Amounts reclassified from accumulated other comprehensive income (loss) and reported in interest expense and related charges		1
Balance at end of period	(18)	(19)
Defined Benefit Pension and OPEB Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(83)	(91)
Defined benefit pension plans (net of tax)	2	1
Amounts reclassified from accumulated other comprehensive income (loss) and reported in interest expense and related charges
Balance at end of period	(81)	(90)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(101)	(111)
Defined benefit pension plans (net of tax)	2	1
Amounts reclassified from accumulated other comprehensive income (loss) and reported in interest expense and related charges		1
Balance at end of period	$ (99)	$ (109)

Pension And OPEB Plans (Narrati

Pension And OPEB Plans (Narrative) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018USD ($)
Oncor Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.53%
Expected return on plan assets	5.13%
Vistra Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.72%
Expected return on plan assets	4.78%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash contributions	$ 42
Additional cash contributions	40
Additional cash contributions, next five years	$ 480
OPEB Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.73%
Expected return on plan assets	6.20%
Cash contributions	$ 27
Additional cash contributions	8
Additional cash contributions, next five years	$ 175

Pension And OPEB Plans (Schedul

Pension And OPEB Plans (Schedule Of Pension And OPEB Plan Costs) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Net costs	$ 37	$ 36	$ 74	$ 72
Less amounts deferred principally as property or a regulatory asset	(18)	(25)	(35)	(51)
Net amounts recognized as expense	19	11	39	21
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	7	6	14	12
Interest cost	30	33	60	66
Expected return on assets	(30)	(29)	(60)	(58)
Amortization of net loss	12	11	24	22
Net costs	19	21	38	42
OPEB Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	2	4	4
Interest cost	11	12	22	24
Expected return on assets	(2)	(2)	(4)	(4)
Amortization of prior service cost	(7)	(5)	(14)	(10)
Amortization of net loss	14	8	28	16
Net costs	$ 18	$ 15	$ 36	$ 30

Related-Party Transactions (Nar

Related-Party Transactions (Narrative) (Details) - Sponsor Group [Member] $ in Millions	Mar. 08, 2018USD ($)
Related Party Transaction [Line Items]
Equity in existing vendor	16.00%
Cash payments to vendors related to Texas margin taxes	$ 35
Capitalized [Member]
Related Party Transaction [Line Items]
Cash payments to vendors related to Texas margin taxes	33
Operation And Maintenance Expense [Member]
Related Party Transaction [Line Items]
Cash payments to vendors related to Texas margin taxes	$ 2

Related-Party Transactions (Sch

Related-Party Transactions (Schedule Of Trade Accounts And Other Receivables From Related Parties) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Trade accounts receivable from TCEH (affiliated)	$ (4)	$ (26)
Texas margin taxes payable	13	21
Net payable (receivable)	9	(5)
Texas [Member]
Related Party Transaction [Line Items]
Texas margin taxes payable	13	21
Federal [Member]
Related Party Transaction [Line Items]
Trade accounts receivable from TCEH (affiliated)	(4)	(26)
Sempra Texas Holdings [Member]
Related Party Transaction [Line Items]
Net payable (receivable)	10
Sempra Texas Holdings [Member] | Texas [Member]
Related Party Transaction [Line Items]
Texas margin taxes payable	13
Sempra Texas Holdings [Member] | Federal [Member]
Related Party Transaction [Line Items]
Trade accounts receivable from TCEH (affiliated)	(3)
EFH Corp [Member] | Texas [Member]
Related Party Transaction [Line Items]
Texas margin taxes payable		21
EFH Corp [Member] | Federal [Member]
Related Party Transaction [Line Items]
Trade accounts receivable from TCEH (affiliated)		(21)
Texas Transmission Investment LLC [Member]
Related Party Transaction [Line Items]
Net payable (receivable)	(1)	(5)
Texas Transmission Investment LLC [Member] | Federal [Member]
Related Party Transaction [Line Items]
Trade accounts receivable from TCEH (affiliated)	$ (1)	$ (5)

Related-Party Transactions (S45

Related-Party Transactions (Schedule Of Related Party Transactions) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Related Party Transaction [Line Items]
Federal income taxes	$ 12	$ (114)
Texas margin taxes	19	18
Total payments (receipts)	31	(96)
Sempra Texas Holdings [Member]
Related Party Transaction [Line Items]
Federal income taxes	29
Texas margin taxes	19
Total payments (receipts)	48
EFH Corp [Member]
Related Party Transaction [Line Items]
Federal income taxes	(19)	(102)
Texas margin taxes		18
Total payments (receipts)	(19)	(84)
Texas Transmission Investment LLC [Member]
Related Party Transaction [Line Items]
Federal income taxes	2	(12)
Total payments (receipts)	$ 2	$ (12)

Supplementary Financial Infor46

Supplementary Financial Information (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Supplemental Financial Information [Line Items]
Aggregate amortization expenses	$ 14	$ 15	$ 26	$ 29
Goodwill	$ 4,064		$ 4,064		$ 4,064
Trade Accounts Receivable [Member] | Nonaffiliated REP [Member]
Supplemental Financial Information [Line Items]
Concentration risk percentage			15.00%		12.00%
Trade Accounts Receivable [Member] | Second Nonaffiliated REP [Member]
Supplemental Financial Information [Line Items]
Concentration risk percentage			12.00%		10.00%

Supplementary Financial Infor47

Supplementary Financial Information (Schedule Of Other Income And (Deductions)) (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017		Jun. 30, 2018	Jun. 30, 2017
Supplementary Financial Information [Abstract]
Professional fees		$ (2)	$ (3)		$ (4)	$ (8)
Sempra Acquisition related costs					(16)
Recoverable pension and OPEB - non-service costs	[1]	(13)	(8)		(27)	(15)
Other, including interest income		(3)			(3)	1
Total other income and (deductions) - net		$ (18)	$ (11)	[2]	$ (50)	$ (22)
[1]	The prior periods have been adjusted to present non-service costs as a non-operating cost pursuant to ASU 2017-07. See Note 1 for additional information.
[2]	As adjusted for the retrospective adoption of ASU 2017-07, as discussed in Note 1.

Supplementary Financial Infor48

Supplementary Financial Information (Schedule Of Interest Expense And Related Charges) (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017		Jun. 30, 2018	Jun. 30, 2017
Supplementary Financial Information [Abstract]
Interest	$ 89	$ 88		$ 178	$ 174
Amortization of debt issuance costs and discounts	2			3	1
Less allowance for funds used during construction — capitalized interest portion	(4)	(3)		(6)	(5)
Total interest expense and related charges	$ 87	$ 85	[1]	$ 175	$ 170
[1]	As adjusted for the retrospective adoption of ASU 2017-07, as discussed in Note 1.

Supplementary Financial Infor49

Supplementary Financial Information (Schedule Of Trade Accounts And Other Receivables) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Supplementary Financial Information [Abstract]
Gross trade accounts and other receivables	$ 690	$ 638
Allowance for uncollectible accounts	(4)	(3)
Trade accounts receivable - net	$ 686	$ 635

Supplementary Financial Infor50

Supplementary Financial Information (Summary of Investments And Other Property) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Supplementary Financial Information [Abstract]
Assets related to employee benefit plans, including employee savings programs	$ 108	$ 111
Land and other investments	10	2
Total investments and other property	$ 118	$ 113

Supplementary Financial Infor51

Supplementary Financial Information (Schedule Of Property, Plant And Equipment) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Supplementary Financial Information [Abstract]
Total assets in service	$ 22,381	$ 21,717
Less accumulated depreciation	7,408	7,255
Net of accumulated depreciation	14,973	14,462
Construction work in progress	512	402
Held for future use	15	15
Property, plant and equipment - net	$ 15,500	$ 14,879

Supplementary Financial Infor52

Supplementary Financial Information (Schedule Of Intangible Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,197	$ 1,132
Accumulated Amortization	461	435
Net	736	697
Land Easements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	454	453
Accumulated Amortization	98	96
Net	356	357
Capitalized Software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	743	679
Accumulated Amortization	363	339
Net	$ 380	$ 340

Supplementary Financial Infor53

Supplementary Financial Information (Schedule Of Estimated Aggregate Amortization Expenses) (Details) $ in Millions	Jun. 30, 2018USD ($)
Supplementary Financial Information [Abstract]
2,018	$ 51
2,019	50
2,020	49
2,021	49
2,022	$ 49

Supplementary Financial Infor54

Supplementary Financial Information (Schedule Of Employee Benefit Obligations And Other) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Supplementary Financial Information [Abstract]
Retirement plans and other employee benefits	$ 1,983	$ 2,035
Investment tax credits	9	10
Other	69	57
Total employee benefit obligations and other	$ 2,061	$ 2,102

Supplementary Financial Infor55

Supplementary Financial Information (Schedule Of Supplemental Cash Flow Information) (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017
Supplementary Financial Information [Abstract]
Interest		$ 172	$ 170
Less capitalized interest		(6)	(5)
Interest payments (net of amounts capitalized)		166	165
Federal	[1]	12	(114)
State	[1]	19	18
Total payments (receipts) in lieu of income taxes	[1]	31	(96)
Noncash construction expenditures	[2]	$ 121	$ 132
[1]	See Note 11 for income tax related detail.
[2]	Represents end-of-period accruals.