Retirement and Deferred Compensation Plans - Schedule of Projected Benefit Payment Estimates (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
2021	$ 65.8
2022	35.6
2023	27.1
2024	25.7
2025	25.0
2026–2029	150.0
Total projected benefit payments	329.2
Retiree health care plan
Defined Benefit Plan Disclosure [Line Items]
2021	1.1
2022	1.1
2023	1.1
2024	1.0
2025	1.0
2026–2029	4.6
Total projected benefit payments	$ 9.9

The total amount of the aggregate benefits expected to be paid.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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

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- Definition

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

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- Definition

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 third 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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