Earnings Per Share (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Basic Earnings (Loss) Per Common Share
Net income (loss) attributable to Unisys Corporation common shareholders	$ 47.8	$ (11.6)	$ (17.8)	$ (25.1)
Weighted average shares	50,245	43,811	49,144	43,883
Total	$ 0.95	$ (0.26)	$ (0.36)	$ (0.57)
Diluted Earnings (Loss) Per Common Share
Net income (loss) attributable to Unisys Corporation common shareholders	47.8	(11.6)	(17.8)	(25.1)
Add preferred stock dividends	0	0	0	0
Net income (loss) attributable to Unisys Corporation for diluted earnings per share	$ 47.8	$ (11.6)	$ (17.8)	$ (25.1)
Weighted average shares	50,245	43,811	49,144	43,883
Plus incremental shares from assumed conversions
Employee stock plans	177
Preferred stock	0	0	0	0
Adjusted weighted average shares	50,422	43,811	49,144	43,883
Total	$ 0.95	$ (0.26)	$ (0.36)	$ (0.57)