Earnings Per Common Share - Computation of Basis and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net loss	$ (5.5)	$ (13.8)	$ (32.4)	$ (22.1)
Preferred stock dividends	2.6	2.6	5.2	5.2
Net loss applicable to common shareowners - basic and diluted	$ (8.1)	$ (16.4)	$ (37.6)	$ (27.3)
Denominator:
Weighted average common shares outstanding - basic	50.4	42.4	50.3	42.4
Stock-based compensation arrangements	0.0	0.0	0.0	0.0
Weighted average common shares outstanding - diluted	50.4	42.4	50.3	42.4
Earnings Per Share, Basic and Diluted	$ (0.16)	$ (0.39)	$ (0.75)	$ (0.64)