CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net income (loss)	$ (7.8)	$ (8.5)	$ (58.9)	$ (23.3)
Amortization of prior service costs (credits)	0.0	0.0	(0.1)	(0.1)
Other comprehensive income (loss), before tax	0.0	0.0	(0.1)	(0.1)
Income tax expense related to items of other comprehensive income	0.0	0.0	0.0	0.0
Other comprehensive income (loss), net of tax	0.0	0.0	(0.1)	(0.1)
Comprehensive income (loss)	$ (7.8)	$ (8.5)	$ (59.0)	$ (23.4)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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

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