v3.10.0.1

FAIR VALUE OF FINANCIAL INSTRUMENTS - Non-Recurring basis (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2018 | Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Goodwill, Impairment Loss | $ 0.7 |
Impairment - Market Assets |  | $ 2.1
Impairment - Assets Held for Sale |  | 26.9
Impairment - Bonneville Assets held for Sale |  | 25.6
Impairment - Other assets held for sale |  | $ 1.3

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