Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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

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

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Income Taxes - Lawrence, Kansas Transaction (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Jan. 12, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income taxes
Valuation allowance for deferred tax assets		$ 128.0		$ 128.0
Net proceeds from sale of assets				213.0
Income tax expense		$ 1.6	$ 2.7	$ (16.4)	$ (7.4)
Lawrence, Kansas System \| MidCo \| Disposal Group Disposed of by Sale, Not Discontinued Operations
Income taxes
Net proceeds from sale of assets	$ 213.0
Income tax expense	11.1
Deferred income tax benefit	$ 36.3