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Income Tax Valuation Allowance (Details6) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2015 USD ($) | Dec. 31, 2015 USD ($) year | Dec. 31, 2014 USD ($) year
Valuation Allowance [Line Items] |  |  |
Valuation allowance for deferred tax assets |  | $ 105.1 | $ 34.4
Number of Years in Cumulative Loss Profit Position | year |  | 3 | 3
Deferred tax asset valuation allowance charge | $ 63.9 | $ 68.4 |
Amount of valuation allowance in the effective tax rate (percent) |  | 4.00% |
Discrete Item [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Deferred tax asset valuation allowance charge |  | $ 49.3 |
Part of Effective Tax Rate [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Deferred tax asset valuation allowance charge |  | 19.1 |
Federal [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Valuation allowance for deferred tax assets |  | 24.8 |
State net operating loss carryforwards [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Valuation allowance for deferred tax assets |  | 61.8 |
Foreign Net Operating Losses and Credits [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Valuation allowance for deferred tax assets |  | 1.4 |
State tax credits [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Valuation allowance for deferred tax assets |  | 13.8 |
State temporary differences [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Valuation allowance for deferred tax assets |  | $ 3.3 |
State [Member] |  |  |
Valuation Allowance [Line Items] |  |  |
Operating loss carryforward period |  | 20 years |
Maximum tax benefit available per year amount |  | $ 5.0 |
Maximum tax benefit available per year percent of income |  | 30.00% |

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- 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=6907707&loc=d3e32537-109319 + Details
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