Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Basic loss per common share computation:
Net loss attributable to Unisys Corporation	$ (40.0)	$ (17.1)	$ (215.4)	$ (74.4)
Weighted average shares (in shares)	68,289	67,694	68,116	67,541
Basic loss per common share (in dollars per share)	$ (0.59)	$ (0.25)	$ (3.16)	$ (1.10)
Diluted loss per common share computation:
Net loss attributable to Unisys Corporation	$ (40.0)	$ (17.1)	$ (215.4)	$ (74.4)
Weighted average shares (in shares)	68,289	67,694	68,116	67,541
Plus incremental shares from assumed conversions of employee stock plans (in shares)	0	0	0	0
Adjusted weighted average shares (in shares)	68,289	67,694	68,116	67,541
Diluted loss per common share (in dollars per share)	$ (0.59)	$ (0.25)	$ (3.16)	$ (1.10)
Stock options and restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive weighted-average stock options and restricted stock units (in shares)	901	418	646	628