Retirement Benefits (Details 14) $ in Millions	Dec. 31, 2023 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2024	$ 12.1
2025	13.3
2026	14.6
2027	16.0
2028	17.0
2029-2033	96.7
Other Postretirement Benefits
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2024	26.5
2025	24.2
2026	22.3
2027	20.6
2028	18.9
2029-2033	71.6
Medicare Part D Subsidy [Abstract]
2024	0.0
2025	0.0
2026	0.0
2027	0.0
2028	0.0
2029-2033	$ 0.0

Defined Benefit Plan Expected Future Benefit Payments [Abstract]

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Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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Amount of prescription drug subsidy receipt expected after fifth fiscal year following current fiscal year.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-URI https://asc.fasb.org//1943274/2147480266/715-60-50-4

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