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v3.19.3.a.u2

Goodwill (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Goodwill [Line Items] |  |
Goodwill | $ 446 | $ 440
CECONY |  |
Goodwill [Line Items] |  |
Goodwill | 245 | 245
O&R |  |
Goodwill [Line Items] |  |
Goodwill | 161 | 161
O&R Merger |  |
Goodwill [Line Items] |  |
Goodwill | 406 | 406
Gas Storage Company | CET Gas |  |
Goodwill [Line Items] |  |
Goodwill | 8 | 8
Residential Solar Company | Clean Energy Businesses |  |
Goodwill [Line Items] |  |
Goodwill | 14 | 14
Battery Storage Company | Clean Energy Businesses |  |
Goodwill [Line Items] |  |
Goodwill |  | $ 12
Goodwill, purchase accounting adjustments | $ 18 |

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