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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Income tax benefit (expense)	$ 48.3	$ (0.9)	$ 50.6	$ 1.9
Helguvik [Member]
Income Tax Contingency [Line Items]
Discrete tax benefit	$ 49.8

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Discrete Tax Benefit (Expense)

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