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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income tax benefit (expense)	$ (6.8)		$ (0.3)	$ 43.8	$ 1.6
Helguvik [Member]
Income Tax Contingency [Line Items]
Discrete tax benefit		$ 49.8

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Discrete Tax Benefit (Expense)

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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