Earnings Per Share (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended			6 Months Ended				12 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010		Jun. 30, 2011	Jun. 30, 2010		Jun. 30, 2011 Stock Options and Restricted Stock Units [Member]	Dec. 31, 2010 Stock Options and Restricted Stock Units [Member]	Jun. 30, 2011 Mandatory Convertible Preferred Stock [Member]
Net (loss) income from continuing operations attributable to Unisys Corporation common shareholders	$ (11.6)	$ 59.2		$ (52.4)	$ 41.9
Income from discontinued operations, net of tax		61.0	[1]		66.7	[1]
Net (loss) income attributable to Unisys Corporation common shareholders	$ (11.6)	$ 120.2	[1]	$ (52.4)	$ 108.6	[1]
Weighted average shares	43,106	42,590		42,971	42,494
Continuing operations	$ (0.27)	$ 1.39	[1]	$ (1.22)	$ 0.99	[1]
Discontinued operations		$ 1.43	[1]		$ 1.57	[1]
Total	$ (0.27)	$ 2.82	[1]	$ (1.22)	$ 2.56	[1]
Employee stock plans		739			862
Adjusted weighted average shares	43,106	43,329		42,971	43,356
Continuing operations	$ (0.27)	$ 1.36	[1]	$ (1.22)	$ 0.96	[1]
Discontinued operations		$ 1.41	[1]		$ 1.54	[1]
Total	$ (0.27)	$ 2.77	[1]	$ (1.22)	$ 2.50	[1]
Antidilutive securities							3,265	2,545	2,588

[1] Reclassified for discontinued operations. See note (a).