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Amounts Receivable (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Receivables [Line Items] |  |
Other receivables | $ 4.7 | $ 5.7
Trade and other current receivables | 37.4 | 39.5
Canada |  |
Receivables [Line Items] |  |
Sales tax receivables | 8.9 | 10.6
Mexico |  |
Receivables [Line Items] |  |
Sales tax receivables | 18.1 | 17.5
Other |  |
Receivables [Line Items] |  |
Sales tax receivables | 5.7 | 3.4
Concentrate receivable | $ 0.0 | $ 2.3

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