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Retirement Benefits Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accrued postretirement benefits	$ 247.8		$ 247.8		$ 258.1
Income tax provision	3.4	$ 4.0	$ 8.3	$ 9.5
Sheffield, UK Operations
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Portion of loss in AOCI	$ 29.5

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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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