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Mergers, Acquisitions and Dispositions Purchase Price allocation Table - Con Edison (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Sep. 01, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Business Combination Segment Allocation [Line Items] |  |  |  |
Payments to Acquire Businesses, Gross |  | $ 154 | $ 208 | $ 6,923
Energy Marketing Contracts Assets, Noncurrent |  | $ 372 | $ 395 |
ConEdison Solutions [Member] |  |  |  |
Business Combination Segment Allocation [Line Items] |  |  |  |
Payments to Acquire Businesses, Gross | $ 257 |  |  |

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- Definition Carrying amount as of the balance sheet date of the asset arising from energy trading activities that involves the purchase and sale of energy under forward contracts at fixed and variable prices and the buying and selling of financial energy contracts that include exchange futures and options and over the counter options and swaps, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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