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Financial Instruments and Risk Management (Currency Contracts) (Details) $ in Millions, $ in Millions, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2020 CAD ($) | Dec. 31, 2020 $ / $ | Dec. 31, 2020 MXN ($) | Dec. 31, 2020 $ / $
Collars and Forwards [Member] |  |  |  |  |  |
Disclosure of detailed information about hedged items [line items] |  |  |  |  |  |
Financial liabilities, at fair value |  | $ 3.3 |  |  |  |
Gains (losses) on change in fair value of derivatives | $ 1.4 | $ (1.5) |  |  |  |
2019 [member] | Collars [Member] | Currency risk [member] |  |  |  |  |  |
Disclosure of detailed information about hedged items [line items] |  |  |  |  |  |
Notional amount |  |  | $ 45.0 |  | $ 1,185.0 |
Bottom of range [member] | 2019 [member] | Collars [Member] | Currency risk [member] |  |  |  |  |  |
Disclosure of detailed information about hedged items [line items] |  |  |  |  |  |
Average rate of hedging instrument |  |  |  | 131.00% |  | 2096.00%
Top of range [member] | 2019 [member] | Collars [Member] | Currency risk [member] |  |  |  |  |  |
Disclosure of detailed information about hedged items [line items] |  |  |  |  |  |
Average rate of hedging instrument |  |  |  | 138.00% |  | 2528.00%

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- Definition The average rate of a hedging instrument. [Refer: Hedging instruments [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 23B -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_23B_b&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The fair value of financial liabilities. [Refer: At fair value [member]; Financial liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_25&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The gains (losses) resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_85&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The nominal or face amount of a financial instrument, used to calculate payments made on that instrument. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard -URIDate 2020-01-01 + Details
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