Supplemental Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Supplemental Financial Information [Line Items]
Cost of goods sold	$ 603.8	$ 643.0	$ 641.8
Research and development costs	14.7	14.8	16.3
Advertising costs	6.8	7.0	6.5
Interest income	(0.3)	(3.2)	(4.3)
Pension and postretirement cost (credits)	358.7	(16.9)	(33.0)
Other	(1.0)	(0.3)	4.8
Total	357.4	(20.4)	(32.5)
Maintenance and Repair Costs [Member]
Supplemental Financial Information [Line Items]
Cost of goods sold	$ 38.1	$ 41.4	$ 41.6

Defined benefit plan net period benefit cost excluding service cost.

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Supplemental financial information.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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-Publisher FASB
-Name Accounting Standards Codification
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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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The net amount of nonoperating interest income (expense).

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of income (expense) related to nonoperating activities, classified as other.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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