Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Basic Loss Per Share
Net loss attributable to Unisys Corporation common shareholders	$ (58.2)	$ (12.1)	$ (101.4)	$ (65.6)
Weighted average shares	49,927	50,843	49,874	48,593
Total	$ (1.17)	$ (0.24)	$ (2.03)	$ (1.35)
Diluted Loss Per Share
Net loss attributable to Unisys Corporation common shareholders	$ (58.2)	$ (12.1)	$ (101.4)	$ (65.6)
Add preferred stock dividends	0.0	0.0	0.0	0.0
Net loss attributable to Unisys Corporation for diluted earnings per share	$ (58.2)	$ (12.1)	$ (101.4)	$ (65.6)
Weighted average shares	49,927	50,843	49,874	48,593
Plus incremental shares from assumed conversions
Employee stock plans	0	0	0	0
Preferred stock	0	0	0	0
Adjusted weighted average shares	49,927	50,843	49,874	48,593
Total	$ (1.17)	$ (0.24)	$ (2.03)	$ (1.35)