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v3.20.4

Derivative - Assets and Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Derivative [Line Items] |  |
Due from affiliates | $ 10.3 | $ 30.1
Due from affiliates - less current portion | 1.7 | 0.5
Due to affiliates | 21.7 | 32.9
Due to affiliates - less current portion | 0.1 | 0.0
Commodity Contract [Member] | Glencore [Member] |  |
Derivative [Line Items] |  |
Due from affiliates | 1.2 | 0.2
Due from affiliates - less current portion | 1.7 | 0.5
Due to affiliates | 11.3 |
Due to affiliates - less current portion | 0.1 |
Not Designated as Hedging Instrument [Member] |  |
Derivative [Line Items] |  |
Asset Fair Value | 15.2 | 19.7
Liability Fair Value | 16.7 | 4.2
Not Designated as Hedging Instrument [Member] | Commodity Contract [Member] |  |
Derivative [Line Items] |  |
Asset Fair Value | 12.8 | 19.7
Liability Fair Value | 16.7 | 3.6
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] |  |
Derivative [Line Items] |  |
Asset Fair Value | 2.4 | 0.0
Liability Fair Value | $ 0.0 | $ 0.6

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