Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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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.

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- Definition

Represents the impact on both basic and diluted net income per common share for recognition of total stock-based compensation expense.

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Number of stock-based compensation plans during the period for the entity.

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Accounting Policies - Stock Based Compensation (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) segment	Dec. 31, 2018 USD ($) item	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) $ / shares	Dec. 31, 2016 USD ($) $ / shares
Stock-based compensation
Number of stock-based compensation plans \| item			1
Total unrecognized compensation costs related to unvested stock-based compensation arrangements	$ 17.4	$ 17.4	$ 17.4	$ 17.4	$ 17.4
Total weighted average remaining term of unrecognized compensation costs	1 year 7 months 10 days
Compensation cost recognized					13.8	$ 13.9	$ 13.4
Number of Reportable Segments		3	3
Impact on both basic and diluted net income per common share for recognition of total stock-based compensation expense (in dollars per share) \| $ / shares				$ 0.32		$ 0.28	$ 0.29
Cost of goods sold.
Stock-based compensation
Compensation cost recognized					0.9	$ 0.8	$ 0.9
Selling, general and administrative expenses
Stock-based compensation
Compensation cost recognized					12.9	13.1	12.5
Stock options
Stock-based compensation
Tax benefit recorded for the compensation expense						0.1	0.8
Other Stock-based Plans
Stock-based compensation
Tax benefit recorded for the compensation expense					$ 2.8	$ 3.9	$ 2.8