Stock and Other Incentive Plans - Amortization of Compensation for Nonvested Shares (Details) $ in Millions	Dec. 31, 2018 USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
2019	$ 8.6
2020	8.1
2021	7.0
2022	4.5
2023	2.3
2024 and thereafter	2.8
Total	$ 33.3

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Next Twelve Months

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- Definition

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Year Five

+ References

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- Definition

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Year Four

+ References

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- Definition

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Year Three

+ References

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- Definition

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Year Two

+ References

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- Definition

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, after Year Five

+ References

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- References

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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