Income Taxes (Unrecognized Tax Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Unrecognized Tax Benefits [Roll Forward]
Unrecognized tax benefits at January 1	$ 30.6	$ 23.1
Increases related to: tax positions taken during a prior period	17.3	11.5
Increases related to: tax positions taken during the current period	0.4	0.3
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	0.0	0.0
Decreases related to: lapse of applicable statute of limitations	(3.0)	(3.2)
Decreases related to: settlements with taxing authorities	0.0	(1.1)
Unrecognized tax benefits at December 31	$ 45.3	$ 30.6

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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