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COMMITMENTS AND CONTINGENCIES (Tables) | 9 Months Ended
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Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract] |
Schedule of regulatory assets and reserves related to manufactured gas plant sites | We have established the following regulatory assets and reserves related to manufactured gas plant sites:
(in millions) |  | September 30, 2017 |  | December 31, 2016
Regulatory assets |  | $ | 683.3 |  |  | $ | 702.7 |
Reserves for future remediation |  | 617.5 |  |  | 633.4 |

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- Definition Tabular disclosure of information about obligations resulting from other commitments. + References No definition available. + Details
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