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Related Party Transactions (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | May 22, 2019
Related Party Transaction [Line Items] |  |  |  |
Net sales to Glencore | $ 1,191.6 | $ 1,204.5 | $ 1,198.1 |
Glencore [Member] |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Net sales to Glencore | 1,191.6 | 1,204.5 | 1,198.1 |
Purchases from Glencore | 323.9 | 319.6 | 253.0 |
BHH [Member] |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Purchases from BHH | $ 17.8 | $ 28.4 | $ 15.8 |
Ownership percentage, equity method |  |  |  | 40.00%

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- Definition Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07.1(c)) -URI http://asc.fasb.org/extlink&oid=116637345&loc=SL114874292-224272 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
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