Employee Benefits Schedule of Expected Benefit Payments for Pension and Other Postretirement Benefits (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension Plan and SERP [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2019	$ 9.0
2020	9.1
2021	7.6
2022	7.5
2023	6.8
2026 through 2030	31.4
Medical Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2019	0.2
2020	0.2
2021	0.1
2022	0.1
2023	0.1
2026 through 2030	$ 0.5

No definition available.

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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