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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, 2024 | Dec. 31, 2023
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | $ (331.4) | $ (242.6)
Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Impact on pre-tax earnings | 14.5 | 10.0
Total financial instrument exposure to credit risk | (144.8) | (88.1)
Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Impact on pre-tax earnings | 5.3 | 1.3
Total financial instrument exposure to credit risk | (48.0) | (12.2)
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 | (18.9) | (25.0)
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 | (11.8) | (12.4)
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 | (24.0) | (13.0)
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 | (35.9) | (14.9)
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 | (10.1) | (38.6)
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 | (153.6) | (124.1)
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 | (17.7) | (16.4)
Income Taxes Payable | Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (3.2) | (0.1)
Income Taxes Payable | Currency risk | Mexican peso |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Total financial instrument exposure to credit risk | (45.6) | (40.2)
Other Monetary (Liabilities) 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 | (66.8) | (16.8)
Other Monetary (Liabilities) 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 | $ (6.6) | $ (6.6)

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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 Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + 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 2024-01-01 -Paragraph 35K -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_35K_a&doctype=Standard -URIDate 2024-03-27 + Details
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