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Financial Instruments and Risk Management (Foreign Currency Exchange Rate Risk) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | $ (153.5) | $ (176.5)
Unrealized gains | $ (0.3) | 0.4
Currency risk |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Potential percentage change in value | 10.00% |
Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | $ (678.2) | (574.7)
Impact on pre-tax earnings | 3.6 | 1.4
Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (13.3) | (58.9)
Impact on pre-tax earnings | 0.3 | 0.4
Cash and cash equivalents | Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (21.6) | (21.3)
Cash and cash equivalents | Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (4.1) | (8.8)
Equity securities | Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk |  | (23.9)
Equity securities | Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | 0.0 | 0.0
Trade receivables | Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (16.6) | (7.9)
Trade receivables | Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (21.5) | (21.0)
Other monetary assets | Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (9.8) | (17.2)
Other monetary assets | Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (0.8) | (0.6)
Accounts Payable And Accrued Liabilities | Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (102.7) | (83.8)
Accounts Payable And Accrued Liabilities | Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (19.3) | (26.1)
Deferred Income Taxes | Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (642.1) | (561.2)
Deferred Income Taxes | Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | $ (18.8) | $ (62.0)

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- Definition Sensitivity Analysis For Types Of Market Risk, Reasonably Possible Change In Risk Variable, Impact On Pre-Tax Earnings + References No definition available. + Details
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- Definition The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2022-03-24 -Paragraph 35K -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_35K_a&doctype=Standard -URIDate 2022-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2023-01-01 -Name IFRS -Number 7 -IssueDate 2022-03-24 -Paragraph 36 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_36_a&doctype=Standard&book=b -URIDate 2022-03-24 + Details
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