Retirement and Deferred Compensation Plans - Projected Benefit Payment Estimates (Details) $ in Millions	Dec. 31, 2018 USD ($)
Pension plans
Defined Benefit Plan Disclosure [Line Items]
2019	$ 12.3
2020	13.2
2021	15.3
2022	16.0
2023	17.9
2024-2028	117.4
Total projected benefit payments	192.1
Retiree health care plan
Defined Benefit Plan Disclosure [Line Items]
2019	1.1
2020	1.1
2021	1.1
2022	1.1
2023	1.1
2024-2028	4.9
Total projected benefit payments	$ 10.4

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

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- Definition

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+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

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

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- Definition

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

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

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

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

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