Statement of Consolidated Shareholders' Deficit (Unaudited) - USD ($) $ in Millions	Total	Preferred Stock:	Common Stock:	Capital Surplus:	Accumulated Deficit:	Accumulated Other Comprehensive Loss:	Amortization of prior net losses	Amortization of prior service credit	Foreign currency translation adjustments	Settlement adjustment	Net actuarial gain	Treasury Stock, At Cost:
Beginning balance at Dec. 31, 2017	$ (353.5)	$ 0.0	$ 0.3	$ 2,323.3	$ (2,228.6)	$ (355.8)						$ (92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	0.2			0.2
Net income (loss)	(14.6)				(14.6)
Change in other comprehensive income							$ 3.8	$ (0.1)	$ (1.7)
Ending balance at Mar. 31, 2018	(365.9)	0.0	0.3	2,323.5	(2,243.2)	(353.8)						(92.7)
Beginning balance at Dec. 31, 2017	(353.5)	0.0	0.3	2,323.3	(2,228.6)	(355.8)						(92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	2.7
Ending balance at Sep. 30, 2018	(328.8)	0.0	0.3	2,326.8	(2,225.9)	(337.3)						(92.7)
Beginning balance at Mar. 31, 2018	(365.9)	0.0	0.3	2,323.5	(2,243.2)	(353.8)						(92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	3.1			3.1
Net income (loss)	14.4				14.4
Change in other comprehensive income							3.8	(0.1)	0.6
Ending balance at Jun. 30, 2018	(344.1)	0.0	0.3	2,326.6	(2,228.8)	(349.5)						(92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	0.2			0.2
Net income (loss)	2.9				2.9
Change in other comprehensive income							3.5	(0.1)	0.9	$ 7.2	$ 0.7
Ending balance at Sep. 30, 2018	(328.8)	0.0	0.3	2,326.8	(2,225.9)	(337.3)						(92.7)
Beginning balance at Dec. 31, 2018	(305.5)	0.0	0.3	2,327.6	(2,208.4)	(332.3)						(92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	1.6			1.6
Net income (loss)	(49.1)				(49.1)
Change in other comprehensive income							3.2	(0.1)	0.4
Ending balance at Mar. 31, 2019	(349.5)	0.0	0.3	2,329.2	(2,257.5)	(328.8)						(92.7)
Beginning balance at Dec. 31, 2018	(305.5)	0.0	0.3	2,327.6	(2,208.4)	(332.3)						(92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(88.7)
Ending balance at Sep. 30, 2019	(380.7)	0.0	0.3	2,332.0	(2,297.1)	(323.2)						(92.7)
Beginning balance at Mar. 31, 2019	(349.5)	0.0	0.3	2,329.2	(2,257.5)	(328.8)						(92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	1.0			1.0
Net income (loss)	(23.6)				(23.6)
Change in other comprehensive income							1.6	(0.1)	0.5
Ending balance at Jun. 30, 2019	(370.1)	0.0	0.3	2,330.2	(2,281.1)	(326.8)						(92.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation	1.8			1.8
Net income (loss)	(16.0)				(16.0)
Change in other comprehensive income							$ 2.5	$ (0.1)	$ (0.8)	$ 1.7	$ 0.3
Ending balance at Sep. 30, 2019	$ (380.7)	$ 0.0	$ 0.3	$ 2,332.0	$ (2,297.1)	$ (323.2)						$ (92.7)