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Business Segments - Geography, Segment Reporting (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	$ 1,836.6	$ 1,893.2	$ 1,589.1
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	1,179.6	1,138.6	938.4
Long-lived assets	419.1	396.0	370.0
Iceland [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	657.0	754.6	650.7
Long-lived assets	518.0	554.3	583.0
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 75.3	$ 76.5	$ 75.0

X

- Definition

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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+ References

No definition available.

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