Net Income Per Share (Schedule of Income Per Share) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Net (loss) from continuing operations	$ (42.3)	$ 340.1	$ (183.6)
Income from discontinued operations			24.7
Net income (loss)	(42.3)us-gaap_NetIncomeLoss	340.1us-gaap_NetIncomeLoss	(158.9)us-gaap_NetIncomeLoss
Net income (loss) if converted - diluted	(42.3)	349.1	(158.9)
Weighted average common shares	9.0	5.0	5.0
Less: Weighted average unvested restricted stock		0.1	0.1
Denominator for basic calculation	9.0	4.9	4.9
Convertible notes		1.8	1.8
Convertible preferred stock - equivalent common shares		27.2	10.3
Convertible preferred stock - less: share issuance limitation		26.3	9.4
Convertible preferred stock - net allowable shares		0.9	0.9
Subtotal		2.7	2.7
Less: shares excluded in a period of net loss or antidilution			2.7
Weighted average effect of dilutive securities		2.7
Denominator for diluted calculation	9.0	7.6	4.9
Income (loss) from continuing operations - per basic share	$ (4.70)	$ 69.41	$ (37.47)
Income (loss) from continuing operations - per diluted share	$ (4.70)	$ 45.93	$ (37.47)
Income per share from discontinued operations - basic and diluted			$ 5.04
Net income (loss) per basic share	$ (4.70)us-gaap_EarningsPerShareBasic	$ 69.41us-gaap_EarningsPerShareBasic	$ (32.43)us-gaap_EarningsPerShareBasic
Net income (loss) per diluted share	$ (4.70)us-gaap_EarningsPerShareDiluted	$ 45.93us-gaap_EarningsPerShareDiluted	$ (32.43)us-gaap_EarningsPerShareDiluted
Convertible Debt [Member]
Debt Instrument [Line Items]
Interest expense		$ 9.0	$ 20.3

Total Common Shares Attributable To Conversion Of Debt Securities

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible preferred stock using the if-converted method.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent, and includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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Number of shares of restricted stock determined by relating the portion of time within a reporting period that restricted shares have been outstanding to the total time in that period. Restricted shares are subject to sales, contractual, regulatory or other restrictions that prevent or inhibit the holder from freely disposing of them before the restriction ends.

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