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Financial Instruments and Risk Management - Credit and Liquidity Risk (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Financial Instruments [Abstract] |  |
Percent of gross accounts receivable over 90 days past due (less than in 2019) | 1.00% | 2.00%
Allowance for doubtful accounts | $ 5.0 | $ 4.2

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- Definition Financial Instruments [Abstract] + References No definition available. + Details
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- Definition Financing Receivable, Percent Past Due2 + References No definition available. + Details
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- Definition The amount of an allowance account used to record impairments to financial assets due to credit losses. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2021-01-01 -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 16 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b -URIDate 2020-01-01 + Details
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Balance Type: | credit
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