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COMMITMENTS AND CONTINGENCIES - ENVIRONMENTAL MATTERS (Details) $ in Millions | 1 Months Ended | 6 Months Ended
--- | --- | ---
Apr. 30, 2019 degreecelsius | Dec. 31, 2018 USD ($) change | Jun. 30, 2019 USD ($) generating_units MW
Manufactured gas plant remediation |  |  |
Regulatory assets |  | $ 3,855.8 | $ 4,035.3
Environmental remediation costs |  |  |
Manufactured gas plant remediation |  |  |
Regulatory assets |  | $ 687.1 | $ 707.6
Mercury and Air Toxics Standards | Electric |  |  |
Air quality |  |  |
Revisions to Mercury and Air Toxics Standards | change |  | 0 |
Climate Change | Electric |  |  |
Air quality |  |  |
Company goal for percentage of carbon dioxide emissions reduction by 2030 |  |  | 40.00%
Long-term company goal for percentage of carbon dioxide emissions reduction by 2050 |  |  | 80.00%
Capacity of coal generation retired since the beginning of 2018 | MW |  |  | 1,800
Climate Change | Electric | Maximum |  |  |
Air quality |  |  |
Global temperature increases limit | degreecelsius | 2 |  |
Steam Electric Effluent Limitation Guidelines | Electric |  |  |
Water quality |  |  |
Number of generating units of OCPP and ERGS | generating_units |  |  | 6
Expected cost to achieve required emissions reductions |  |  | $ 70.0
Manufactured Gas Plant Remediation | Natural gas |  |  |
Manufactured gas plant remediation |  |  |
Reserves for future remediation |  | $ 616.4 | 631.8
Manufactured Gas Plant Remediation | Natural gas | Environmental remediation costs |  |  |
Manufactured gas plant remediation |  |  |
Regulatory assets |  | $ 687.1 | $ 707.6

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