Retirement Benefits (Details 14) $ in Millions	Dec. 31, 2021 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2022	$ 161.2
2023	160.8
2024	158.5
2025	156.3
2026	153.9
2027-2031	724.3
Other Postretirement Benefits
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2022	29.2
2023	28.4
2024	26.4
2025	24.5
2026	22.5
2027-2031	86.6
Medicare Part D Subsidy [Abstract]
2022	0.1
2023	0.1
2024	0.1
2025	0.1
2026	0.1
2027-2031	$ 0.2

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