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Financial Instruments and Risk Management - Foreign Currency Sensitivity Analysis (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Borrowings | $ 0 | $ 0
New credit facility |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Borrowings | $ 470,400,000 |
Currency risk |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Reasonably possible change in risk variable, percentage | 1.00% |
Currency risk | Canadian dollar |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Reasonably possible increase in risk variable, impact on net earnings | $ 0 |
Reasonably possible increase in risk variable, impact on other comprehensive income | 1,100,000 |
Reasonably possible decrease in risk variable, impact on net earnings | 0 |
Reasonably possible decrease in risk variable, impact on other comprehensive income | (1,000,000.0) |
Currency risk | Euro |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Reasonably possible increase in risk variable, impact on net earnings | (100,000) |
Reasonably possible increase in risk variable, impact on other comprehensive income | (100,000) |
Reasonably possible decrease in risk variable, impact on net earnings | 100,000 |
Reasonably possible decrease in risk variable, impact on other comprehensive income | 100,000 |
Currency risk | Thai baht |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Reasonably possible increase in risk variable, impact on net earnings | (100,000) |
Reasonably possible increase in risk variable, impact on other comprehensive income | 700,000 |
Reasonably possible decrease in risk variable, impact on net earnings | 100,000 |
Reasonably possible decrease in risk variable, impact on other comprehensive income | (700,000) |
Currency risk | Chinese renminbi |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |
Reasonably possible increase in risk variable, impact on net earnings | (200,000) |
Reasonably possible increase in risk variable, impact on other comprehensive income | 400,000 |
Reasonably possible decrease in risk variable, impact on net earnings | 200,000 |
Reasonably possible decrease in risk variable, impact on other comprehensive income | $ (300,000) |

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