Variable Interest Entities	12 Months Ended
Variable Interest Entities	Dec. 31, 2011
Variable Interest Entities	Note Q — Variable Interest Entities The Companies have not identified any interests they have in any variable interest entity (VIE) that would require the Companies to include the financial position and results of operations of the VIE in the Companies' consolidated financial statements. The accounting rules for consolidation address the consolidation of a VIE by a business enterprise that is the primary beneficiary. A VIE is an entity that does not have a sufficient equity investment at risk to permit it to finance its activities without additional subordinated financial support, or whose equity investors lack the characteristics of a controlling financial interest. The primary beneficiary is the business enterprise that has the power to direct the activities of the VIE that most significantly impact the VIE's economic performance and either absorbs a significant amount of the VIE's losses or has the right to receive benefits that could be significant to the VIE. Con Edison enters into arrangements including leases, partnerships and electricity purchase agreements, with various entities. As a result of these arrangements, Con Edison retains or may retain a variable interest in these entities. CECONY has a variable interest in a non-consolidated VIE, Astoria Energy, LLC (Astoria Energy), with which CECONY has entered into a long-term electricity purchase agreement. CECONY is not the primary beneficiary of this VIE since CECONY does not have the power to direct the activities that CECONY believes most significantly impact the economic performance of Astoria Energy. In particular, CECONY has not invested in, or guaranteed the indebtedness of, Astoria Energy and CECONY does not operate or maintain Astoria Energy's generating facilities. CECONY also has long-term electricity purchase agreements with the following five potential VIEs: Sithe/Independence Power Partners, LP, Cogen Technologies Linden Venture, LP, Selkirk Cogen Partners, LP, Brooklyn Navy Yard Cogeneration Partners, LP, and Indeck Energy Services of Corinth, Inc. In 2011, requests were made of these five counterparties for information necessary to determine whether the entity was a VIE and whether CECONY is the primary beneficiary; however, the information was not made available. See Note I for information on these electricity purchase agreements, the payments pursuant to which constitute CECONY's maximum exposure to loss with respect to Astoria Energy and the five potential VIEs. Con Edison has a variable interest in a non-consolidated VIE, Pilesgrove Solar, LLC (Pilesgrove), in which Con Edison Development, starting in 2010, participated with a third party to develop, construct, and operate a photovoltaic solar energy generation project. The project was constructed for approximately $90 million and commenced commercial operation in August 2011. Con Edison is not the primary beneficiary of this VIE since the power to direct the activities that most significantly impact the economics of Pilesgrove is shared equally between Con Edison Development and the third party. Included in the Con Edison's consolidated balance sheet at December 31, 2011 is $43 million in assets related to Pilesgrove which represents the investment of Con Edison Development. The current maximum exposure to loss in Pilesgrove is $29 million.
CECONY [Member]
Variable Interest Entities	Note Q Variable Interest Entities The Companies have not identified any interests they have in any variable interest entity (VIE) that would require the Companies to include the financial position and results of operations of the VIE in the Companies' consolidated financial statements. The accounting rules for consolidation address the consolidation of a VIE by a business enterprise that is the primary beneficiary. A VIE is an entity that does not have a sufficient equity investment at risk to permit it to finance its activities without additional subordinated financial support, or whose equity investors lack the characteristics of a controlling financial interest. The primary beneficiary is the business enterprise that has the power to direct the activities of the VIE that most significantly impact the VIE's economic performance and either absorbs a significant amount of the VIE's losses or has the right to receive benefits that could be significant to the VIE. Con Edison enters into arrangements including leases, partnerships and electricity purchase agreements, with various entities. As a result of these arrangements, Con Edison retains or may retain a variable interest in these entities. CECONY has a variable interest in a non-consolidated VIE, Astoria Energy, LLC (Astoria Energy), with which CECONY has entered into a long-term electricity purchase agreement. CECONY is not the primary beneficiary of this VIE since CECONY does not have the power to direct the activities that CECONY believes most significantly impact the economic performance of Astoria Energy. In particular, CECONY has not invested in, or guaranteed the indebtedness of, Astoria Energy and CECONY does not operate or maintain Astoria Energy's generating facilities. CECONY also has long-term electricity purchase agreements with the following five potential VIEs: Sithe/Independence Power Partners, LP, Cogen Technologies Linden Venture, LP, Selkirk Cogen Partners, LP, Brooklyn Navy Yard Cogeneration Partners, LP, and Indeck Energy Services of Corinth, Inc. In 2011, requests were made of these five counterparties for information necessary to determine whether the entity was a VIE and whether CECONY is the primary beneficiary; however, the information was not made available. See Note I for information on these electricity purchase agreements, the payments pursuant to which constitute CECONY's maximum exposure to loss with respect to Astoria Energy and the five potential VIEs. Con Edison has a variable interest in a non-consolidated VIE, Pilesgrove Solar, LLC (Pilesgrove), in which Con Edison Development, starting in 2010, participated with a third party to develop, construct, and operate a photovoltaic solar energy generation project. The project was constructed for approximately $90 million and commenced commercial operation in August 2011. Con Edison is not the primary beneficiary of this VIE since the power to direct the activities that most significantly impact the economics of Pilesgrove is shared equally between Con Edison Development and the third party. Included in the Con Edison's consolidated balance sheet at December 31, 2011 is $43 million in assets related to Pilesgrove which represents the investment of Con Edison Development. The current maximum exposure to loss in Pilesgrove is $29 million.

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

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+ Details