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Assets and Liabilities Held for Sale (Tables) | 9 Months Ended
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Sep. 30, 2020
Assets and Liabilities Held for Sale [Abstract] |
Disposal Groups, Including Discontinued Operations [Table Text Block] | The major classes of assets and liabilities classified as held for sale on the Condensed Consolidated Balance Sheets (unaudited) at September 30, 2020 were:
(in millions) |  |  |  |  |  |  |  |  |
Assets Held for Sale | Net Property, Plant and Equipment |  | Total Current Assets |  | Total Other Assets |  | Loss on Classification as Held for Sale(1) |  | Total Assets Held for Sale
Gas Distribution Operations | 1,705.0 |  |  | 161.5 |  |  | 91.8 |  |  | (392.6) |  |  | 1,565.7 |
Liabilities Held for Sale | Long-term Debt, Excluding Amounts Due Within One Year |  | Total Current Liabilities |  | Total Other Liabilities |  | Total Liabilities Held for Sale
Gas Distribution Operations | 41.6 |  |  | 60.1 |  |  | 350.1 |  |  | 451.8 |
(1) Amount differs from that presented in the Condensed Statements of Consolidated Income (Loss) (unaudited) due to cash already paid for certain transaction costs.
Disposal Groups, Pretax Income (Loss) | The Massachusetts Business had the following pretax income (loss) for the three and nine months ended September 30, 2020 and 2019:
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions) |  | 2020 |  | 2019 |  | 2020 |  | 2019
Pretax Income (Loss) |  | ($74.1) |  | ($55.2) |  | ($402.9) |  | $183.5

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