Income Taxes - Effective Tax Rate Reconciliation (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Reconcilation [Line Items]
Income tax expense (benefit) at U.S. federal statutory rate	$ (9.2)	$ 2.4	$ (73.0)
Income tax expense on noncontrolling interest earnings not taxable to the Company	(22.0)	(22.5)	0
State and foreign tax expense, net of federal tax	(3.1)	1.7	(4.8)
Increase in deferred tax asset valuation allowance	36.7	21.9	865.5
Amount allocated to other comprehensive income	0	(22.7)	0
Change in accrual for uncertain tax positions	(0.9)	(1.7)	0
Stock compensation in excess of tax deduction	2.0	3.1	0
Expiration of charitable contribution carryforwards	0	2.5	0
Other permanent differences	4.2	4.9	2.3
Income tax expense (benefit)	$ 7.7us-gaap_IncomeTaxExpenseBenefit	$ (10.4)us-gaap_IncomeTaxExpenseBenefit	$ 790.0us-gaap_IncomeTaxExpenseBenefit

Amount of tax benefit (expense) allocated to other comprehensive income (loss).

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit or to total foreign income tax expense or benefit.

+ References

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

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-Number 210

-Section 08

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to noncontrolling interest income (loss) exempt from income taxes.

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