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Assets and Liabilities Held for Sale Assets and Liabilities Held for Sale (Tables) | 3 Months Ended
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Mar. 31, 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 March 31, 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 | 1,641.2 |  |  | 200.4 |  |  | 88.7 |  |  | (274.5 | ) |  | 1,655.8 |
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 | 42.4 |  |  | 78.9 |  |  | 349.6 |  |  | 470.9 |
(1) Amount differs from that presented in the Condensed Statements of Consolidated Income (unaudited) due to cash already paid for certain transaction costs.

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