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Income Taxes Deferred Tax Asset Valuation Allowance (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	$ 322.2	$ 105.1
Federal Net Operating Losses [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	37.8	0.0
Federal Tax Credits [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	40.5	24.8
Federal Temporary Differences [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	141.2	0.0
Federal Deferred Tax Assets [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	219.5	24.8
State Net Operating Losses [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	77.9	61.8
State Tax Credits [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	13.3	13.8
State Temporary Differences [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	6.5	3.3
State Deferred Tax Assets [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	97.7	78.9
Foreign Deferred Tax Assets [Member]
Valuation Allowance [Line Items]
Valuation allowance for deferred tax assets	$ 5.0	$ 1.4

X

- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319

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+ References

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