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Financial Instruments and Risk Management (Fair Value And Presentation in the Balance Sheet) (Details) - Derivatives - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Disclosure of detailed information about financial instruments [line items]
Financial assets, at fair value	$ (4.3)	$ 3.0
Currency Hedging Derivative Instruments
Disclosure of detailed information about financial instruments [line items]
Financial assets, at fair value		2.6
Financial liabilities, at fair value	(4.3)
Fuel Options
Disclosure of detailed information about financial instruments [line items]
Financial assets, at fair value	0.0	0.4
Gold Options
Disclosure of detailed information about financial instruments [line items]
Financial assets, at fair value		$ 0.5
Financial liabilities, at fair value	$ 0.1

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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.

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- Definition

The fair value of financial assets. [Refer: At fair value [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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