Derivative - Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Due to affiliates	$ 17.0	$ 65.8
Due to affiliates - less current portion	8.3	21.9
Commodity Contract \| Glencore
Derivative [Line Items]
Due to affiliates	11.9		$ 17.1
Due to affiliates - less current portion	8.3		$ 21.9
Not Designated as Hedging Instrument
Derivative [Line Items]
Asset Fair Value	129.1	42.9
Liability Fair Value	31.0	146.2
Not Designated as Hedging Instrument \| Commodity Contract
Derivative [Line Items]
Asset Fair Value	129.1	42.9
Liability Fair Value	23.7	143.3
Not Designated as Hedging Instrument \| Foreign Exchange Contract
Derivative [Line Items]
Asset Fair Value	0.0	0.0
Liability Fair Value	$ 7.3	$ 2.9

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables owed to an entity that is affiliated with the reporting entity by means of direct or indirect ownership, which are usually due after one year (or one business cycle, if longer).

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