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Retirement Benefits Narrative (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Jul. 31, 2021
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Settlement loss (gain)	$ 0.0		$ (64.9)	$ 0.0	$ (64.9)
Accrued postretirement benefits	243.1			243.1		$ 258.1
Income tax provision	3.0		22.0	11.3	31.5
Collective-Bargaining Arrangement, Other
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Income tax provision			15.5
Sheffield, UK Operations
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Portion of loss in AOCI		$ 29.5
Pension Plans Defined Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Settlement loss (gain)	0.0		0.0	29.5	0.0
Other Postretirement Benefit Plan, Defined Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Settlement loss (gain)	$ 0.0		$ (64.9)	$ 0.0	$ (64.9)
Other Postretirement Benefit Plan, Defined Benefit | Collective-Bargaining Arrangement, Other
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accrued postretirement benefits							$ 43.0
Accumulated other comprehensive (income) loss, before tax							$ 21.9

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